Help With Spawning A Projectile

I'm trying to restore the scrapped Iceologer mob for a mod I'm making, and I need help with the summoning of an Ice Chunk projectile.

The basic idea is this: When the Iceologer gets hurt, it summons an Ice Chunk a few blocks above the player that attacked it. However, I can only find stuff that shoots projectiles directly from the mob. Anyone know how to do this, or at the very least know a workaround?