ZK has collapsed, how are the four kings of Layer 2 doing now?
The project that once taught us the first lesson on the blockchain is now also trying to catch up to survive.Author: Airdrop Insulator Scof, ChainCatcher
Editor: TB, ChainCatcher
Event Summary
On the evening of April 15, the ZKsync token ZK experienced an abnormal drop, falling over 14% within 24 hours, with the price briefly dropping below $0.04. Following the incident, exchanges such as Bithumb suspended ZK's deposit and withdrawal services.
According to on-chain data, the actual attack occurred on April 13 at 8 PM (UTC+8). The attacker used an admin account of an airdrop distribution contract to call the sweepUnclaimed() function, minting approximately 111 million unclaimed airdrop tokens. Subsequently, the attacker sold about 66 million tokens and conducted cross-chain transfers. By the time the incident was exposed on April 15, approximately 44.68 million tokens remained in the attacker's address.
At 9 PM on April 15, the community first disclosed this abnormal behavior of issuance and selling on social platforms. The ZKsync team responded shortly after, confirming that this was due to the leakage of the admin keys of three airdrop distribution contracts, leading to abnormal minting behavior. The official statement indicated that this incident only involved the airdrop contracts and did not affect the ZKsync protocol itself, the main ZK token contract, governance contracts, or other token distribution plans. The token circulation increased by approximately 0.45%, with a total value of about $5 million.
The ZKsync team coordinated with exchanges on the night of the incident to attempt to freeze the relevant funds and called on the attacker to return the tokens to avoid legal consequences. The official emphasized that this attack vector could no longer be exploited, and the rest of the current system remained unaffected.
After the incident, the price of the ZK token briefly rebounded but has not returned to pre-incident levels. As of now, the investigation is still ongoing, and the project team has stated that further details will be released.
From Former Kings to "Heaven's Fall"?
Once regarded as the "Four Kings" of Ethereum Layer 2—ZKsync, Arbitrum, Optimism, and Starknet—their trajectories have now diverged significantly. Notably, many of my peers began their on-chain operations through the airdrops of these projects, learning basic concepts such as wallets, interactions, and gas fees. These projects not only carried the technical practices of Ethereum's scalability but also became the entry point for many into the crypto world.
ZKsync and Starknet both belong to the ZK Rollup route and were once seen as representatives of the technical faction, emphasizing higher security and data validity. ZKsync promoted its zkEVM compatible with EVM, aiming to reuse Ethereum ecosystem tools to lower development barriers, while Starknet insisted on its self-developed Cairo language system, achieving higher performance potential but limiting its ecosystem expansion. In contrast, Arbitrum and Optimism adopted the earlier implemented OP Rollup solution, relying on optimistic proofs for transaction settlement, allowing for quicker market entry in terms of development toolchains and compatibility.
In terms of ecosystem development, Arbitrum is undoubtedly the strongest performer currently, with native DeFi projects like GMX firmly established and a richer overall application layer distribution. Optimism's pace is more focused on governance and architectural expansion, launching OP Stack and collaborating with Coinbase to launch the Base mainnet, which has initially constructed a "modular alliance chain" framework. Meanwhile, ZKsync's ecosystem heat has largely stagnated around the time of the airdrop, with several projects running away after the airdrop, severely damaging user and developer confidence. Starknet's development pace has been relatively slow, and its ecosystem expansion has lagged behind.
In terms of user activity, Arbitrum has long been in the lead, with both on-chain active addresses and transaction volumes far exceeding the others, followed closely by Optimism. ZKsync peaked during the airdrop but quickly saw a drop in activity, with current daily active users at a low point. Starknet's data has remained stable for a long time but lacks growth, consistently struggling to break through.
The on-chain locked value also visually reflects the differences between projects. According to DefiLlama data, Arbitrum firmly holds the top position in L2 TVL with $2.1 billion, demonstrating a certain economic self-circulation capability; Optimism maintains high expectations due to the expansion potential of OP Stack; ZKsync's revenue has been persistently low, with TVL only fluctuating at a few event nodes, lacking long-term growth momentum; Starknet similarly faces issues of insufficient scale, with both revenue and locked value being small.
From the data on capital bridging, the differences in ecosystem activity among projects are also very evident. According to Dune data, Arbitrum's official cross-chain bridge has accumulated over 4 million ETH bridged, firmly in first place among all Layer 2 projects; ZKsync follows closely with approximately 3.7 million ETH, which may seem substantial at first glance, but activity has clearly declined. In the past 7 days, only 14 users utilized the ZKsync official bridge, with a total bridging amount of just 5 ETH, nearly at a standstill. In contrast, the total bridging amounts for Optimism and Starknet have not been high, remaining below 1 million ETH.
However, it is worth noting that despite Arbitrum's robust performance in the on-chain ecosystem, with sustained user activity and project implementation, its token price trend has not been ideal. Since its peak of about $2.4 last year, the ARB price has retraced over 88%, yet its current market capitalization remains above $1.3 billion. This discrepancy may be closely related to its continuously released circulating supply. Since the token's launch, Arbitrum has seen multiple large unlocks, resulting in persistent market selling pressure and price pressure.
Once the "Four Kings" of Layer 2, they represented both the future direction of Ethereum's scalability and the first stop for countless users entering the market. However, after experiencing technological implementation, airdrop battles, security incidents, and project differentiation, today's Layer 2 landscape is no longer marked by glory.
The once-repeated emphasis on "high performance, low cost, strong security" seems to be losing its appeal. How much longer can the narratives that use Layer 2 as an entry point hold up? In the current environment of capital and attention flowing out, is Layer 2 truly a bridge to large-scale applications, or merely a transitional solution? Will the projects that were once highly anticipated ultimately stall in the middle of technological evolution?
