Tier 1
🟢 water breathing, vision, mining
🟢 spiky to punch (thorns effect)
🟢 natural armor - leather
🔴 slowness when out of water
🔴 still sink
🔴 burning in hot biomes/nether
🔴 weakness to fire damage
🔴 weak weapons
🔴 cannot wear armor
🔴 cannot use swords
Tier 2
🟢 Stinging Coral - 10% chance to poison on hit
🟢 Knockback resistance
🟢 natural armor - iron
Tier 3
🟢 Haste in water
🟢 Hits now give slow
🟢 natural armor - diamond
Tier 4
🟢 Poison becomes Wither
🟢 no more burning in nether/hot biomes
🟢 natural armor - diamond
Tier 2 = Kill an Elder Guardian
Tier 3 = Make and place a Conduit
Tier 4 = Kill a Wither and take its Star