關於 use scenario ，我們在網路上蒐集到這些相關的討論、資訊與評價

I like the following write up and agree with its statements:

What exactly is Pi? In 2009, when Bitcoin was first released, 50 coins could be mined for free every 10 minutes. Most people found it worthless. At the all-time high (ATH), one Bitcoin was worth almost $63,000. When Litecoin was released in 2011, 100 LTC could be mined for free every day. Most people still think that it is worthless. At its ATH, one Litecoin was worth $300. When Ethereum was first released in 2014, 30 ETH could be mined for free every day. At its recent ATH, one Ethereum was worth $4000.

With the development of mobile internet technology, everyone's life is becoming more and more digital. Cryptocurrency is not only an outlet for entrepreneurs or investors, but an era for all! Pi is a free cryptocurrency network that everyone can join. Anyone can start mining by downloading the application of the Picoin official website with their mobile phone. All Picoins are mined by the user themselves. You can click on mining every 24 hours, and it’s completely free, just like original Bitcoin mining, but it's more convenient and simpler than before.

Looking at the growth of Bitcoin and Ethereum, it can be painful. Two huge opportunities have passed. Many people regret missing out!

No problem! You are reading this writeup and you have learned of the 3rd chance, and its name is Pi Network.

Pi Network is a 100% FREE cryptocurrency project of the Stanford University team of doctors. Pi Network was created with cryptocurrency universal to all users around the world, unlike Bitcoin which is difficult to use and difficult to access to most of the population.

Just own a phone and take 10 seconds of attendance every day and persevere. No crashes, no RAM, you can mine cryptocurrency Pi Network automatically, for free every day. Just like Bitcoin and Ethereum when they were first launched.

The Pi Network project is at the end of its testing phase and is preparing to go public on the mainnet (expected this year end). Currently, if you mine alone, you receive 6pi per day, 180 pi per month. I have been mining Pi since 2019, and have accumulated 19k Pi coins.

If at the end of this year, Pi is priced at 1 USD -> You and I have money for coffee. And as time progresses...
If Pi costs 10USD -> You and I have money to spend.
If Pi costs 100USD -> You and I will be wealthy.
….
If Pi costs 0 USD -> You don’t lose any money. You just wasted your time clicking the “mine Pi” button once a day. However, this scenario is unlikely as the current Pi user base has passed 18 million and is growing rapidly. Pi is a project where we are likely to win. The project is FREE at no cost to you!

—————————-
If you are not registered with PI NETWORK, click the following link:
https://minepi.com/miltongohblog

Use my invitation code to access Pi Network app and you will receive 1 Pi coin as a welcome gift!
Invitation code: miltongohblog

📜 [專欄新文章] Uniswap v3 Features Explained in Depth

✍️ 田少谷 Shao

📥 歡迎投稿： https://medium.com/taipei-ethereum-meetup #徵技術分享文 #使用心得 #教學文 #medium

Once again the game-changing DEX 🦄 👑

Image source: https://uniswap.org/blog/uniswap-v3/

Outline

0. Intro1. Uniswap & AMM recap2. Ticks 3. Concentrated liquidity4. Range orders: reversible limit orders5. Impacts of v36. Conclusion

0. Intro

The announcement of Uniswap v3 is no doubt one of the most exciting news in the DeFi place recently 🔥🔥🔥

While most have talked about the impact v3 can potentially bring on the market, seldom explain the delicate implementation techniques to realize all those amazing features, such as concentrated liquidity, limit-order-like range orders, etc.

Since I’ve covered Uniswap v1 & v2 (if you happen to know Mandarin, here are v1 & v2), there’s no reason for me to not cover v3 as well ✅

Thus, this article aims to guide readers through Uniswap v3, based on their official whitepaper and examples made on the announcement page. However, one needs not to be an engineer, as not many codes are involved, nor a math major, as the math involved is definitely taught in your high school, to fully understand the following content 😊😊😊

If you really make it through but still don’t get shxt, feedbacks are welcomed! 🙏

There should be another article focusing on the codebase, so stay tuned and let’s get started with some background noise!

1. Uniswap & AMM recap

Before diving in, we have to first recap the uniqueness of Uniswap and compare it to traditional order book exchanges.

Uniswap v1 & v2 are a kind of AMMs (automated market marker) that follow the constant product equation x * y = k, with x & y stand for the amount of two tokens X and Y in a pool and k as a constant.

Comparing to order book exchanges, AMMs, such as the previous versions of Uniswap, offer quite a distinct user experience:

AMMs have pricing functions that offer the price for the two tokens, which make their users always price takers, while users of order book exchanges can be both makers or takers.

Uniswap as well as most AMMs have infinite liquidity¹, while order book exchanges don’t. The liquidity of Uniswap v1 & v2 is provided throughout the price range [0,∞]².

Uniswap as well as most AMMs have price slippage³ and it’s due to the pricing function, while there isn’t always price slippage on order book exchanges as long as an order is fulfilled within one tick.

In an order book, each price (whether in green or red) is a tick. Image source: https://ftx.com/trade/BTC-PERP

¹ though the price gets worse over time; AMM of constant sum such as mStable does not have infinite liquidity

² the range is in fact [-∞,∞], while a price in most cases won’t be negative

³ AMM of constant sum does not have price slippage

2. Tick

The whole innovation of Uniswap v3 starts from ticks.

For those unfamiliar with what is a tick:

Source: https://www.investopedia.com/terms/t/tick.asp

By slicing the price range [0,∞] into numerous granular ticks, trading on v3 is highly similar to trading on order book exchanges, with only three differences:

The price range of each tick is predefined by the system instead of being proposed by users.

Trades that happen within a tick still follows the pricing function of the AMM, while the equation has to be updated once the price crosses the tick.

Orders can be executed with any price within the price range, instead of being fulfilled at the same one price on order book exchanges.

With the tick design, Uniswap v3 possesses most of the merits of both AMM and an order book exchange! 💯💯💯

So, how is the price range of a tick decided?

This question is actually somewhat related to the tick explanation above: the minimum tick size for stocks trading above 1$ is one cent.

The underlying meaning of a tick size traditionally being one cent is that one cent (1% of 1$) is the basis point of price changes between ticks, ex: 1.02 — 1.01 = 0.1.

Uniswap v3 employs a similar idea: compared to the previous/next price, the price change should always be 0.01% = 1 basis point.

However, notice the difference is that in the traditional basis point, the price change is defined with subtraction, while here in Uniswap it’s division.

This is how price ranges of ticks are decided⁴:

Image source: https://uniswap.org/whitepaper-v3.pdf

With the above equation, the tick/price range can be recorded in the index form [i, i+1], instead of some crazy numbers such as 1.0001¹⁰⁰ = 1.0100496621.

As each price is the multiplication of 1.0001 of the previous price, the price change is always 1.0001 — 1 = 0.0001 = 0.01%.

For example, when i=1, p(1) = 1.0001; when i=2, p(2) = 1.00020001.

p(2) / p(1) = 1.00020001 / 1.0001 = 1.0001

See the connection between the traditional basis point 1 cent (=1% of 1$) and Uniswap v3’s basis point 0.01%?

Image source: https://tenor.com/view/coin-master-cool-gif-19748052

But sir, are prices really granular enough? There are many shitcoins with prices less than 0.000001$. Will such prices be covered as well?

Price range: max & min

To know if an extremely small price is covered or not, we have to figure out the max & min price range of v3 by looking into the spec: there is a int24 tick state variable in UniswapV3Pool.sol.

Image source: https://uniswap.org/whitepaper-v3.pdf

The reason for a signed integer int instead of an uint is that negative power represents prices less than 1 but greater than 0.

24 bits can cover the range between 1.0001 ^ (2²³ — 1) and 1.0001 ^ -(2)²³. Even Google cannot calculate such numbers, so allow me to offer smaller values to have a rough idea of the whole price range:

1.0001 ^ (2¹⁸) = 242,214,459,604.341

1.0001 ^ -(2¹⁷) = 0.000002031888943

I think it’s safe to say that with a int24 the range can cover > 99.99% of the prices of all assets in the universe 👌

⁴ For implementation concern, however, a square root is added to both sides of the equation.

How about finding out which tick does a price belong to?

Tick index from price

The answer to this question is rather easy, as we know that p(i) = 1.0001^i, simply takes a log with base 1.0001 on both sides of the equation⁴:

Image source: https://www.codecogs.com/latex/eqneditor.php

Let’s try this out, say we wanna find out the tick index of 1000000.

Image source: https://ncalculators.com/number-conversion/log-logarithm-calculator.htm

Now, 1.0001¹³⁸¹⁶² = 999,998.678087146. Voila!

⁵ This formula is also slightly modified to fit the real implementation usage.

3. Concentrated liquidity

Now that we know how ticks and price ranges are decided, let’s talk about how orders are executed in a tick, what is concentrated liquidity and how it enables v3 to compete with stablecoin-specialized DEXs (decentralized exchange), such as Curve, by improving the capital efficiency.

Concentrated liquidity means LPs (liquidity providers) can provide liquidity to any price range/tick at their wish, which causes the liquidity to be imbalanced in ticks.

As each tick has a different liquidity depth, the corresponding pricing function x * y = k also won’t be the same!

Each tick has its own liquidity depth. Image source: https://uniswap.org/blog/uniswap-v3/

Mmm… examples are always helpful for abstract descriptions 😂

Say the original pricing function is 100(x) * 1000(y) = 100000(k), with the price of X token 1000 / 100 = 10 and we’re now in the price range [9.08, 11.08].

If the liquidity of the price range [11.08, 13.08] is the same as [9.08, 11.08], we don’t have to modify the pricing function if the price goes from 10 to 11.08, which is the boundary between two ticks.

The price of X is 1052.63 / 95 = 11.08 when the equation is 1052.63 * 95 = 100000.

However, if the liquidity of the price range [11.08, 13.08] is two times that of the current range [9.08, 11.08], balances of x and y should be doubled, which makes the equation become 2105.26 * 220 = 400000, which is (1052.63 * 2) * (110 * 2) = (100000 * 2 * 2).

We can observe the following two points from the above example:

Trades always follow the pricing function x * y = k, while once the price crosses the current price range/tick, the liquidity/equation has to be updated.

√(x * y) = √k = L is how we represent the liquidity, as I say the liquidity of x * y = 400000 is two times the liquidity of x * y = 100000, as √(400000 / 100000) = 2.

What’s more, compared to liquidity on v1 & v2 is always spread across [0,∞], liquidity on v3 can be concentrated within certain price ranges and thus results in higher capital efficiency from traders’ swapping fees!

Let’s say if I provide liquidity in the range [1200, 2800], the capital efficiency will then be 4.24x higher than v2 with the range [0,∞] 😮😮😮 There’s a capital efficiency comparison calculator, make sure to try it out!

Image source: https://uniswap.org/blog/uniswap-v3/

It’s worth noticing that the concept of concentrated liquidity was proposed and already implemented by Kyper, prior to Uniswap, which is called Automated Price Reserve in their case.⁵

⁶ Thanks to Yenwen Feng for the information.

4. Range orders: reversible limit orders

As explained in the above section, LPs of v3 can provide liquidity to any price range/tick at their wish. Depending on the current price and the targeted price range, there are three scenarios:

current price < the targeted price range

current price > the targeted price range

current price belongs to the targeted price range

The first two scenarios are called range orders. They have unique characteristics and are essentially fee-earning reversible limit orders, which will be explained later.

The last case is the exact same liquidity providing mechanism as the previous versions: LPs provide liquidity in both tokens of the same value (= amount * price).

There’s also an identical product to the case: grid trading, a very powerful investment tool for a time of consolidation. Dunno what’s grid trading? Check out Binance’s explanation on this, as this topic won’t be covered!

In fact, LPs of Uniswap v1 & v2 are grid trading with a range of [0,∞] and the entry price as the baseline.

Range orders

To understand range orders, we’d have to first revisit how price is discovered on Uniswap with the equation x * y = k, for x & y stand for the amount of two tokens X and Y and k as a constant.

The price of X compared to Y is y / x, which means how many Y one can get for 1 unit of X, and vice versa the price of Y compared to X is x / y.

For the price of X to go up, y has to increase and x decrease.

With this pricing mechanism in mind, it’s example time!

Say an LP plans to place liquidity in the price range [15.625, 17.313], higher than the current price of X 10, when 100(x) * 1000(y) = 100000(k).

The price of X is 1250 / 80 = 15.625 when the equation is 80 * 1250 = 100000.

The price of X is 1315.789 / 76 = 17.313 when the equation is 76 * 1315.789 = 100000.

If now the price of X reaches 15.625, the only way for the price of X to go even higher is to further increase y and decrease x, which means exchanging a certain amount of X for Y.

Thus, to provide liquidity in the range [15.625, 17.313], an LP needs only to prepare 80 — 76 = 4 of X. If the price exceeds 17.313, all 4 X of the LP is swapped into 1315.789 — 1250 = 65.798 Y, and then the LP has nothing more to do with the pool, as his/her liquidity is drained.

What if the price stays in the range? It’s exactly what LPs would love to see, as they can earn swapping fees for all transactions in the range! Also, the balance of X will swing between [76, 80] and the balance of Y between [1250, 1315.789].

This might not be obvious, but the example above shows an interesting insight: if the liquidity of one token is provided, only when the token becomes more valuable will it be exchanged for the less valuable one.

…wut? 🤔

Remember that if 4 X is provided within [15.625, 17.313], only when the price of X goes up from 15.625 to 17.313 is 4 X gradually swapped into Y, the less valuable one!

What if the price of X drops back immediately after reaching 17.313? As X becomes less valuable, others are going to exchange Y for X.

The below image illustrates the scenario of DAI/USDC pair with a price range of [1.001, 1.002] well: the pool is always composed entirely of one token on both sides of the tick, while in the middle 1.001499⁶ is of both tokens.

Image source: https://uniswap.org/blog/uniswap-v3/

Similarly, to provide liquidity in a price range < current price, an LP has to prepare a certain amount of Y for others to exchange Y for X within the range.

To wrap up such an interesting feature, we know that:

Only one token is required for range orders.

Only when the current price is within the range of the range order can LP earn trading fees. This is the main reason why most people believe LPs of v3 have to monitor the price more actively to maximize their income, which also means that LPs of v3 have become arbitrageurs 🤯

I will be discussing more the impacts of v3 in 5. Impacts of v3.

⁷ 1.001499988 = √(1.0001 * 1.0002) is the geometric mean of 1.0001 and 1.0002. The implication is that the geometric mean of two prices is the average execution price within the range of the two prices.

Reversible limit orders

As the example in the last section demonstrates, if there is 4 X in range [15.625, 17.313], the 4 X will be completely converted into 65.798 Y when the price goes over 17.313.

We all know that a price can stay in a wide range such as [10, 11] for quite some time, while it’s unlikely so in a narrow range such as [15.625, 15.626].

Thus, if an LP provides liquidity in [15.625, 15.626], we can expect that once the price of X goes over 15.625 and immediately also 15.626, and does not drop back, all X are then forever converted into Y.

The concept of having a targeted price and the order will be executed after the price is crossed is exactly the concept of limit orders! The only difference is that if the range of a range order is not narrow enough, it’s highly possible that the conversion of tokens will be reverted once the price falls back to the range.

As price ranges follow the equation p(i) = 1.0001 ^ i, the range can be quite narrow and a range order can thus effectively serve as a limit order:

When i = 27490, 1.0001²⁷⁴⁹⁰ = 15.6248.⁸

When i = 27491, 1.0001²⁷⁴⁹¹ = 15.6264.⁸

A range of 0.0016 is not THAT narrow but can certainly satisfy most limit order use cases!

⁸ As mentioned previously in note #4, there is a square root in the equation of the price and index, thus the numbers here are for explantion only.

5. Impacts of v3

Higher capital efficiency, LPs become arbitrageurs… as v3 has made tons of radical changes, I’d like to summarize my personal takes of the impacts of v3:

Higher capital efficiency makes one of the most frequently considered indices in DeFi: TVL, total value locked, becomes less meaningful, as 1$ on Uniswap v3 might have the same effect as 100$ or even 2000$ on v2.

The ease of spot exchanging between spot exchanges used to be a huge advantage of spot markets over derivative markets. As LPs will take up the role of arbitrageurs and arbitraging is more likely to happen on v3 itself other than between DEXs, this gap is narrowed … to what extent? No idea though.

LP strategies and the aggregation of NFT of Uniswap v3 liquidity token are becoming the blue ocean for new DeFi startups: see Visor and Lixir. In fact, this might be the turning point for both DeFi and NFT: the two main reasons of blockchain going mainstream now come to the alignment of interest: solving the $$ problem 😏😏😏

In the right venue, which means a place where transaction fees are low enough, such as Optimism, we might see Algo trading firms coming in to share the market of designing LP strategies on Uniswap v3, as I believe Algo trading is way stronger than on-chain strategies or DAO voting to add liquidity that sort of thing.

After reading this article by Parsec.finance: The Dex to Rule Them All, I cannot help but wonder: maybe there is going to be centralized crypto exchanges adopting v3’s approach. The reason is that since orders of LPs in the same tick are executed pro-rata, the endless front-running speeding-competition issue in the Algo trading world, to some degree, is… solved? 🤔

Anyway, personal opinions can be biased and seriously wrong 🙈 I’m merely throwing out a sprat to catch a whale. Having a different voice? Leave your comment down below!

6. Conclusion

That was kinda tough, isn’t it? Glad you make it through here 🥂🥂🥂

There are actually many more details and also a huge section of Oracle yet to be covered. However, since this article is more about features and targeting normal DeFi users, I’ll leave those to the next one; hope there is one 😅

If you have any doubt or find any mistake, please feel free to reach out to me and I’d try to reply AFAP!

Stay tuned and in the meantime let’s wait and see how Uniswap v3 is again pioneering the innovation of DeFi 🌟

Uniswap v3 Features Explained in Depth was originally published in Taipei Ethereum Meetup on Medium, where people are continuing the conversation by highlighting and responding to this story.

👏 歡迎轉載分享鼓掌

【政策簡單說】創新百百種 聽過跨域創新嘸?— #基石者 篇

不知道大家還記不記得小編🙋‍♀️上次提到的 #跨域生態創新？
小編來快速幫大家複習一下 #生態系 組成

一個生態系中會有許多不同的角色參與，包含了：
基石者( #keystone )➡生態系領導角色，創建生態系平台基本雛型，維持整個生態系的核心企業

是不是對基石者的概念還是有點模糊？
「#第29期中小企業趨勢監測報」以 #室內裝修生態系 為例，說明 設計師如何賦能平台整合業主、設計師、施工團隊三方溝通並透過平台跨域整合生活智慧科技，提供優質創新服務😉

那另一位成員 #利基者（#Niche_Player）呢? 咱們下期揭曉!

💁‍♀️全文下載及其他精彩內容傳送門
https://www.apecscmc.org/publication

Previously on the #ECO, we mention what an ECO is and how to promote it. This time, we would like to give a brief introduction to participants in the ECO.

#keystone -> the ECO leader who creates the basic prototype of the ecosystem platform and acts as the core business that sustains the entire ecosystem.

Is keystone still unfamiliar with you?

In the APEC SME Monitor Issue 29, we use the interior decoration ecosystem as an example and explain that how this communication platform creates a triple-win scenario and integrates smart life technology.

Article download and more articles, please click here
💁‍♀️https://www.apecscmc.org/publication

主持人：楊應超
第一季－第5集：美國大選對股市的影響
節目直播時間：週五 14點
本集播出日期：2020.10.09

⏭ 章節：
00:00 頻道片頭
00:07 開場
00:27 節目片頭
00:45 美國大選對股市的影響
14:50 Q＆A：看什麼投資書比較好？
31:28 Q＆A：賺錢比存錢重要
39:33 請繼續提問：你活著不是為了工作，祝大家早日達到財務自由
42:36 節目片尾

📝 名詞補充：
1. Recession：經濟蕭條
2. GDP：國內生產總值
3. Nancy Pelosi：美國眾議院院長
4. House of Representatives：美國眾議院
5. Senate：美國參議院
6. Roth IRA：羅斯IRA (不是傳統IRA)，美國退休帳戶
7. Noise：分析中不重要的雜音訊息
8. Fixed Income：固定收入
9. Zero-Sum Game：零和遊戲
10. Natural Hedge：自然避險
11. Charles Schwab–ETF：QQQ, SPY, DIA
12. Anticipate：預測未來的情況
13. Scenario analysis：場景分析

📚 參考書訊：
1.《財務自由的人生：跟著首席分析師楊應超學華爾街的投資技巧和工作效率，40歲就過FIRE的優質生活》 https://eslite.me/w24ad
2.《Principles: Life and Work》Ray Dalio Principle 橋水基金創始人投資法則書 https://pse.is/wj4qb
3.《MONEY Master the Game: 7 Simple Steps to Financial Freedom》Tony Robbins 安東尼羅賓理財書 https://pse.is/xduqp
4.《One Up On Wall Street: How To Use What You Already Know to Make Money in the Market》Peter Lynch著 https://pse.is/vtgdw

#楊應超 #財務自由 #FIRE


-----
訂閱【豐富】YouTube頻道：https://www.youtube.com/c/豐富
按讚【豐富】FB：https://www.facebook.com/RicherChannel

🔥支付寶打賞：13581883245
🔥王炳忠今日頭條：搜索「王炳忠台灣」
🔥王炳忠臉書粉專：https://www.facebook.com/bingzhong.wang
♦♦♦
“Are you helping or harming us?” This is my serious question to you American politicians, including those in the Trump administration and in the Congress. As the spokesperson for the New Party, one of Taiwan’s political parties, and also a young man who has lived in Taiwan for more than 32 years since my birth, I should tell you that the answer decides our future without doubt. In other words, the very fact I must confirm is whether you support Taiwan independence instead of the One-China policy or just deploy Taiwan as your pawn to bargain with Beijing. To be honest, as you always take it for granted to sacrifice others for your benefits, it is quite important for us to make sure in advance.

As we all know, the US Congress usually tends to challenge China’s sovereignty over Taiwan because of the impact of the military-industrial complex and the lobbies hired by the Taiwan government. The Taiwan Travel Act and the TAIPEI Act are the late instances. However, without the administration’s implementation, these are only lip service. Thus, the administration’s attitude is crucial indeed. So, let’s see the Department of State. As Secretary Pompeo stated last March, the US is now using every tool in its tool kit to prevent China from isolating Taiwan through diplomatic channels. This year, after shifting blames for its neglect of the pandemic prevention by attacking China and the WHO, the Department of State recently expressed support for Taiwan’s participation in the WHA. The above really triggered my curiosity: The establishment of the US-Taiwan formal diplomatic relations is just the most useful tool, isn’t it? Why does the US not use that? Besides, since Taiwan should become a formal member of the UN before entering the WHO, why does the US not recognize Taiwan as a sovereign state or the ROC government in Taiwan as the only legal government of China instead of the PRC?

The answer to my question seems that your real intention is not to support Taiwan’s real independence but only to trouble Beijing. Just as Pompeo said at a congressional hearing, the Trump administration’s way of viewing the US-Taiwan relations can consider the threat of China’s rise more than the predecessors, which reveals that Taiwan is only a chess piece for Washington to play with Beijing. Furthermore, since the US has no will to have Taiwan as a formal ally, Taiwan is just a pawn you can sacrifice anytime. Consequently, Taiwan must suffer the worsening of cross-strait relations at our own cost while the US just plays Taiwan to bargain with Beijing for your own interests. The outcome is so predictable that Taiwan should go through a depression for its large economic dependence on mainland China which you are unable and unwilling to make up. Besides, we should even consider the most serious situation that a war occurs in the Taiwan Strait. The scenario of Taiwan military is holding on alone within two to three weeks in order to wait for the US military aid. Nevertheless, as the former AIT chairman Richard Bush said, the implied commitment of the US to come to Taiwan’s defense has never be absolute. In other words, we should risk engaging a war with Beijing resulted from your dangerous game, sacrificing our lives for your lies.

As I already told you earlier, the real threat to the US is not China’s rise but the loss of your self-confidence. Moreover, you have weakened the stability across the Taiwan Strait by inciting Taiwan to deny the 1992 consensus and intervening in Taiwan’s campaign last year, which destroys the status quo and your interests indeed. Certainly, as what Secretary Pompeo has told us, “We lied, we cheated, we stole,” how can we bet our future on the US “glory” of lying, cheating, and stealing? In fact, as you once betrayed us in 1978 even though the ROC government in Taiwan and your government was formal alliance then, it is much easier for you today to abandon us when the deal has been done.

In conclusion, as your government declared plainly in the U.S.-PRC Joint Communique (1972), the US had its interests in a peaceful settlement of the Taiwan question by the Chinese themselves. Accordingly, since you are not willing to recognize either Taiwan as an independent state or the ROC as the legal government of China, we have no choice but to deal with the question of reunification with Beijing by the Chinese ourselves. Helping instead of harming us, you could stop intervening in the Taiwan question, otherwise it will only strengthen the risk across the Taiwan Strait and put us in jeopardy. Thank you if you release your hands.

Location: If you keep in touch with Shinra intern Chadley during Chapter 8, he should provide you with a VR combat scenario that pits you against summon creature Shiva to earn its respective Materia. Chadley can be found standing between a healing bench and the Materia shop in the Sector 5 Slums.
As a note, you'll have whoever's in your party when you take on this fight, so if you try it with just Cloud, it'll be tougher than if you tackle it with Aerith in your squad. We recommend that you bring Aerith along, though.


Boss Strategy: Shiva is an Ice summon, and thus weak to Fire. Give Aerith your best Fire Materia, and make sure you have the Ifrit summon equipped, then head into the battle. Cloud can pretty much take care of himself, so you're better off controlling Aerith to run up her ATB bars as quickly as possible; the more Fire or Fira spells you can cast on Shiva, the faster you'll manage to stagger her. Make use of Aerith's Arcane Ward ability, which automatically makes you cast two spells for every ATB bar you spend, to maximize your damage. A good Fire spell will knock Shiva to the ground, offering Cloud a chance to lay down some melee attacks. Make sure you're not too close when she gets back up, though, because she'll use the Icicle Impact area attack spell around her when she's back on her feet.
You'll want to keep laying down spells on Shiva while working to keep Aerith alive. You'll need to be on top of dodging her attacks to stay clear of incoming danger, which include Blizzara spells that Shiva will shoot your way and a bunch of ice crystals to shoot at you in a group. Dodging the ice crystals attack is a losing battle because there are so many of them, so guard against it and power through.