Even though axolotls spawn in water, pufferfish still sting them unlike all other aquatic mobs (including glow squids).
MC-233133
Pufferfish sting axolotls even though they are aquatic mobs
Resolved
Works As Intended
0
This is intentional due to the fix of MC-208663. Pufferfish will defend themselves when being attacked causing the axolotl to be harmed in the process.