What Is a “Difficulty Bomb” and What Is Its Purpose in Some Blockchains?

A difficulty bomb is a mechanism intentionally coded into a blockchain protocol that causes the mining difficulty to increase exponentially over time. Its primary purpose is to force a scheduled protocol upgrade, typically from a Proof-of-Work (PoW) consensus to a Proof-of-Stake (PoS) system.

By making mining impossibly difficult and unprofitable, it incentivizes miners to support the network's transition. Once the upgrade is successful, the difficulty bomb is usually defused or removed from the new protocol version.