Ok, so not too long ago for VIP there was "Elemental Hammers" as a VIP item, which involved all kinds of hammers with knockback, poison(slow+constant hp loss), shock(stun), burn, and shadow warp. Might have missed one. ANYwho, there was one hammer called an Ice Hammer which involved the slow debuff, but i think with a higher slow chance. Idk. while this seems appropriate for an ice debuff, i have an idea for a better version, for the Ice Hammer and any ice based items in the future that may have the debuff.
How about a slipping effect, like when the water on era freezes, and you slip with inertia? But not quick, so its not uncontrollable and you cant catch someone, more like its too hard to control which direction they run away to? I think it would be pretty entertaining to watch people slip while they try to attack you back, but have no footing or like try and stop, but cannot??? Huhuhu....
Just an idea, since ice debuff is kinda weak compared to all others in my opinion.