原文来源：DODO Research
Original author: dt
With the arrival of the Bitcoin mining reward halving, this round of bull market was started by the BTC ETF narrative, and also ushered in a large wave of pullbacks due to the imminent landing of the BTC halving, and now the BTC ecological pattern is very different from half a year ago, VC institutions are actively entering the game, in addition to the meme inscription owners of community-driven fair launches, there are also many venture capital institutions or exchange-led BTC L2 or re-pledge chain and other public chain projects have emerged.
In this week's CryptoSnap Dr.DODO, we will take you to know the five currently popular BTC-related public chains and the capital support behind them.
BounceBit
BounceBit is a company that uses the value of BTC as its security foundation and advertises to expand the use of Bitcoin through its restaking mechanism$BB and recently announced that its token $BB will be launched on Binance's Web3 wallet token issuance platform Megadrop The new BTC project has caused an influx of more users and funds.
BounceBit is different from other BTC L2 With the security of Bitcoin Chain technology, BounceBit focuses on building an independent POS public chain on the value of BTC, and through cooperation with CeFi asset management institutions, the BTC managed by users can get an extra layer of income in the form of fee arbitrage, and the $BBTC credentials obtained by users can be used to run BounceBit Chain nodes or obtain $BB in the form of LST protocol In addition to the introduction of the restaking mechanism, other applications in the BounceBit ecosystem can also rely on the $BBTC in the node to complete other verification work, such as oracles, cross-chain bridges and other applications.
At present, BounceBit is still in the process of earning points by depositing wBTC, BTCB and other assets, and said that it will continue until the start of Metadrop.
Source: https://www.binance.com/zh-CN/research/projects/bouncebit
Merlin Chain
Merlin Chain is the highest TVL among the five projects introduced today, which has exceeded $950M so far, and is the first BTC EVM L2 to launch the mainnet, and its token $MERL has also been listed on leading exchanges such as OKX and Bybit in recent days following the Bitcoin halving event.
Invested by The Sparta Group and OKX Ventures, Merlin Chain is a Layer2 solution built on top of Bitcoin, using OP-Rollup and ZK-Rollup in parallel, calling it optimistic ZK-Rollup, and introducing an off-chain decentralized oracle network (Oracle) as a DAC (Data Availability Committee) committee to address data availability issues. Specifically, Merlin's sequencer sends transaction data to Oracle nodes (using lumoz's Prover as a Service service), and Oracle nodes are responsible for verifying ZK Proof and publishing the verification results to the Bitcoin chain (ZK-Rollup), and since the Bitcoin chain cannot fully verify ZK Proof, so the Fraud Proof Mechanism was introduced to allow others to challenge the verification process (OP-Rollup) to ensure the security of the network.
Source: https://docs.merlinchain.io/merlin-docs/architecture
Merlin's ecological projects are also the best developed among BTC L2 at present, among which the asset management protocol Solv Funds, the lending protocol Avalon Finance, and the DEX protocol MerlinSwap TVL have all exceeded the 100M threshold, but it is necessary to continue to pay attention to whether there will be a need for more airdrop hunters to receive funds after the successful issuance of coins in $MERL.
Source: https://defillama.com/chain/Merlin
B² Network
B² Network is also a BTC EVM Layer2 project, invested by Hashkey Captial, OKX Ventures, Kucoin Lab and other institutions The solution extends Polygon CDK to BTC, and enables users to use both EVM wallet accounts and BTC wallet accounts to interact through account abstraction, while taking care of users with ecological habits on both sides, and because BTC cannot store large data data, B² Network has built a layer of DA Layer B² Node and plans to upgrade B² Node to B² in the future Hub, which provides other developers with a data availability layer and state verification/proof system based on the Bitcoin network, enabling them to build their own Bitcoin Rollups using Polygon CDK and B² Hub.
The biggest difference between B² Network and other BTC Layer 2 is that its vision is not limited to a BTC Layer 2, but has the same ambition as Cosmos Hub or Op Stack, and becomes a BTC Layer 2 hub through B² Hub.
Source: https://docs.bsquared.network/architecture
At present, B² Network has also launched the mainnet at the same time as the BTC halving, the first phase of the lock-up airdrop has ended, and the second phase of random airdrop is underway, users only need to bridge BTC to the B² Network mainnet to have the opportunity to get the airdrop when the protocol token is released, there is no clear time limit for this activity, the official only states that it will end at any time.
BOB
BOB (Build On Bitcoin) is also a BTC EVM Layer 2 project, which was invested by Castle Island and Coinbase Ventures, and raised $10 million in the seed round.
In BOB's roadmap, BOB divides its technology into three phases, the first phase of BOD L2 will use OP Stack to launch the mainnet in the form of Ethereum OP Rollup, settlement will take place in Ethereum, and track the state of Bitcoin through Bitcoin light nodes, verify block headers and accept transaction inclusion proofs to achieve trustless cross-chain operations.
Source: https://docs.gobob.xyz/docs/learn/bob-stack/roadmap
The second phase will introduce Bitcoin PoW security, using a new merge mining protocol OptiMine, to separate block production from PoW, and after the BOB sequencer processes transactions and blocks, Bitcoin miners verify the BOB Rollup state, and only when the state transition is correct will the miners take the commitment as part of the PoW, minimizing the trust in the sequencer, and finally the sequencer submits the data covering the PoW commitment to Ethereum, and uses Ethereum as the DA Layer to verify the availability of the data.
Source: https://docs.gobob.xyz/docs/learn/bob-stack/roadmap
The third phase will introduce Bitcoin as a settlement layer, BOB's goal is to introduce Bitcoin as a settlement layer (currently under research), and the possible solution is to introduce ZK compression as a deceptive _proofing, as part of the process to work with ZK infrastructure providers, and design BOB light clients, build bidirectional bridges and extend BitVM programs, and finally implement BOB Rollup state verification.
These three phases illustrate BOB's path from the initial optimistic Ethereum rollup, to the introduction of Bitcoin PoW security, and finally to Bitcoin as the settlement layer. Through this progressive hybrid design, BOB aims to inherit the security of Bitcoin and the programmability of Ethereum, providing an innovative Layer-2 solution for the Bitcoin DeFi ecosystem.
Source: Source: https://docs.gobob.xyz/docs/learn/bob-stack/roadmap
At present, BOB is carrying out the first quarter of the points event, depositing tBTC, WBTC or stablecoins and ETH LST and other tokens can get points rewards, but with the halving event landing, it is officially announced that the mainnet will be launched on 4/24, when the first season of the event will stop and start the second season of points activities, the details have not yet been disclosed.
Mezo
Mezo, which recently announced a $21M funding round led by Pantera Capital and with the participation of top venture capitalists such as Multicoin and Hack VC, is a new Bitcoin public chain developed by the Thesis team that built the BTC wrapped asset tBTC, describing themselves as the "economic layer" of Bitcoin, and will be committed to creating an application ecosystem based on the economic needs of users, focusing on the expansion of BTC application scenarios, and calling its consensus mechanism Proof of HODL, which secures the network by users locking BTC and MEZO tokens and executing CometBFT consensus verification transactions.
Similarly, Mezo is also running a HODL points campaign, allowing users to deposit native BTC, WBTC, or tBTC to earn points. There are not many technical details disclosed by Mezo at the moment, and all deposits in Mezo are kept in a locked contract, which is controlled by the team to hold funds until the Mezo mainnet is bridged when the mainnet is launched.
Source: https://info.mezo.org/proof-of-hodl
Author's point of view
The public chain narrative is always the track with the most grand narrative and the highest valuation and the most financing in the blockchain ecology, and many institutions are therefore reluctant to miss this wave of bull market with the rising Bitcoin narrative, and have launched various public chain projects linked to the concept of Bitcoin.
From the author's point of view, these BTC-related public chain tracks are more important than how to realize the technical logic behind them, and the injection of resources behind them is the market where various institutions play capital, which is a new chain for retail investors, and the target of speculation is nothing more than MEME, DEX or lending mining.
Therefore, in the author's opinion, more ways to participate may be to judge the gold content of the capital behind each project and participate in activities such as airdrop lock-up points in advance to obtain free tokens.