Negator creep

Not too strong but is IMMUNE completely to almost all special effects and elements (elements still deal damage but the after effect is removed) so it requires The damage of the pregectile itself to kill it, also at a higher level (level 7+) it can give nearby creeps resilience (but it's only reduced) bosses cannot be effected by this.

So basically it cannot be effected by slow/freeze/burn/piercing/Explosive/ect, nor special abilities