Flashbots SUAVE testnet shifts block builder market

SUAVE takes the builder lead

Flashbots’ SUAVE testnet deployment has overtaken Eden Network in the block builder market. Before this, Eden Network’s relay saw higher average block rewards because two specific builders sent all their bids to that single relay. I see the SUAVE architecture, which unbundles the mempool and block builder role, as a functional way to address builder centralization. SUAVE works through three parts: the "Preference Environment", the "Execution Market", and the "decentralized block building network". This system allows validators, users, and third-party executors to maximize revenue while reducing economic centralization pressure on each domain. Currently, four builder entities control 70% of all execution block rewards. One builder, Beaverbuild, produced more than 50% of Ethereum blocks in a recent period. This concentration of power creates systemic risks for Ethereum’s network neutrality. Philip Daian announced the SUAVE vision at Devcon in Bogota to decentralize the block-building process. Approximately 90% of validators subscribe to the Flashbots relay, and 78% of MEV-Boost blocks use the Flashbots relay.

The $2,820 MEV-Burn redistribution

The $2,820 September MEV-Burn redistribution follows this shift in market dominance. This mechanism auctions the right to determine transaction order via an in-protocol burn. The winner selects a block hash and commits to burning an amount of ETH at least equivalent to their bid. This process moves MEV from validator profits to a protocol burn, which mirrors the EIP-1559 fee mechanism. This redistribution targets the "Scourge" phase of the Ethereum roadmap to reduce economic concentration. I consider the redirection of these billions of dollars in annual MEV revenue to the protocol as the best way to boost $ETH scarcity. Proposers must pick the top bid because they face the direct opportunity cost of their block being ignored if they choose a lower, non-compliant bid from a censoring builder during the bidding period at the start of the slot.

During the 4-second bidding period of a 16-second slot, eligible proposers broadcast bids containing a proposer index, randao reveal, block hash, amount, and signature. The probability of being an eligible proposer is B/N, where B is the target number of eligible proposers and N is the number of active validators. At t=4, nodes stop listening to bids, and the rest of the slot proceeds normally. From t=4 to t=8, multiple blocks may be revealed by eligible proposers. Nodes verify that the builder’s balance is greater than or equal to the builder fee. The Execution Tickets proposal auctions a single ticket during each block to grant the winning bidder the exclusive right to sequence transactions. While this provides deflationary pressure, it does not eliminate the economic incentives for searchers to sandwich users.

Validator rewards and market trends

The redistribution changes how you view validator rewards. While top-tier validators see lower total yields, the playing field levels for solo stakers who lack sophisticated MEV-boost software. I find the reduction in the incentive to reorg the chain the clearest benefit, as burning MEV removes the motivation to steal the previous block’s value. This shift makes the validator set more stable across different market conditions, which helps with Single Slot Finality. You should note that this does not eliminate the economic incentives for searchers to sandwich users.

Flashbots remains the dominant coordination layer for the transaction supply chain. MEV Blocker, created by the CoW Protocol team, uses a different approach. It uses a rebate mechanism where searchers compete in an auction to backrun a transaction. The winning bid returns to the user, providing savings for DeFi power users that range from a few cents to several dollars. Flashbots Protect instead focuses on preventing bad MEV by letting users submit transactions to a private relay. Flashbots has run since 2021 and maintains extensive builder relationships. I recommend the Flashbots ecosystem for those needing deep builder participation and mature relay integrations. The market favors the system with the deepest integration. Will the increasing concentration of builders eventually render these burn auctions obsolete?