Alpha Yeti

The Alpha Yeti must be defeated to access the glacier biome. It is immune to bows. It can throw ice blocks that can slow you. After a couple of sword strikes, the yeti starts to flail about, knocking all players within range back and damaging them.

In Minecraft version 1.7.10, when the Alpha Yeti flails about he is vulnerable to and can take damage from a Bow (later versions untested). It is not known if this is a bug.