What if a cartel of block builders starts censoring Ethereum?
A builder cartel censoring transactions and extracting predatory MEV attacks Ethereum's credible-neutrality, prompting an emergency protocol response — ETH -4.2% on a slow erosion of trust rather than an acute crash. Conceptually a centralization-of-block-production risk long flagged around PBS/MEV-Boost relay concentration. This is a governance/structural re-rate, not a liquidation event; the price impact is muted because it plays out over months via protocol patches, not in a single session.
Every number ships with its receipt — the odds, the range, the precedents, and a public grade at Reality Check. The statistical machinery that produces it is proprietary.
The butterfly cascade
How this trigger trickles across markets, left → right — the root shock, its first‑order moves, then the ripple effects. Drag any node; tap a market for its real price history.
Resolution timeline — how this probability is moving
Our model's odds (electric blue) over time vs the market's (Polymarket, amber), from the past toward the 6–18 months horizon. Each dot is a real macro event that nudged the probability — green pushed it up, red pushed it down. Tap a dot for the source. Loading the probability audit trail…
What it would mean
If this plays out, it is a risk-off shock. A cartel of block builders censors transactions and extracts predatory MEV, prompting an emergency protocol response and exodus. The trigger decomposes into signed root‑shocks — Crypto confidence ▼ · Risk appetite ▼ — which propagate through our causal graph to the markets below.