I think my plan with them is to make natural spawns hostile, defending a structure they'd spawn in. However, if the mob is built by the player, it would be friendly towards the player and attack hostile mobs as well as entities that hurt its creator.
Thank you! I think depending on how it's spawned will dictate if it's friendly or hostile :3! I definitely want to have player built Whistlers just be able to wander around for the most part, it'd be so cute!
It's all fun and games until a Villager accidentally gets in the crossfire- then all that's left is to hear the awful sound of iron smashing a giant pot until it's nothing but a pile of bricks hahaha