Boss AI Tweaks

Boss AI Tweaks reworks the Wither's fight rather than adding a new mob. The Wither's blue skulls home in on their target, and the boss regenerates health only when it deals damage to a target. It enrages once it loses 25% of its health from a single attack, and while enraged it attacks twice as fast and shoots four times as fast. Projectile immunity is removed, and arrows deal 50% less damage only while the boss is below 50% health. The attack visuals are reworked, and the phase 2 shield effect is repurposed as a charging animation.

The fight has four phases. Phase 1 has the boss hover in place, following the player when it drifts too far away or too close. Phase 2 starts below 83% health and adds a slanted slam that spawns a pool of harm, which on hard difficulty creates a creeper-sized explosion when mob griefing is enabled. Phase 3 starts below 66% health, with the boss strafing around the player and firing blue skulls along with occasional slams. Phase 4 starts below 50% health, with the boss hovering closer and gaining a dash attack similar to the Bedrock Wither's, leaving trail explosions when mob griefing is enabled. Defeating the enraged boss drops two Nether Stars.

Files are available for the Fabric and NeoForge loaders targeting 1.21.1, and for Forge targeting 1.20.1. Entity type tags and NBT data additions from datapacks are kept, and the mod keeps the mob-ai-tweaks namespace other mods use, while its own namespace is boss ai tweaks.