Mob nie może nas bić

on damage:
	if victim is player:
		if attacker is zombie named "&cZombie":
			cancel event

on damage:
	if victim is zombie named "&cZombie":
		cancel event

command /setspawnzombie:
	trigger:
		set {loczombi} to location of player

command /spawnzombie:
	trigger:
		spawn 1 zombie at {loczombi}
		set display name of last spawned entity to "&cZombie"
		apply slowness of tier 255 to last spawned entity for 1000 days 

Liczę na +

Nie potrzebujesz żadnego skryptu, użyj tagów NBT:

/summon Zombie ~0 ~0 ~0 {Invulnerable:1,NoAI:1}