Hearthpwn

To understand Cube Hunter, a more accurate name than Deathrattle Hunter, Cube Hunter is like every other cube deck, where every minion in the deck should have some tempo combo mechanic. Animal Companion is a perfect example of this. Every beast from Animal Companion has a tempo combo mechanic - taunt, buff aura, and charge. This perfectly mirrors the Cube Warlock trio of Voidlord, Malganis, and Doomguard. A tempo combo mechanic guarantees value from cube and deathrattles.

This implies egg does not fit the deck. Play Dead is not a keep in mulligan, except already with egg, because Play Dead is much more powerful in the late game with cube and powerful deathrattles. It is also a situational card - bad against aggro. Terrorscale Stalker is a keep in mulligan because it can be played for tempo.

Although egg may not fit the deck of Cube Hunter, the deck does have to play like an aggro deck because of the lack of control tools in hunter however. Egg is a relatively powerful early game minion which puts a lot of early or mid game pressure.

The name of Cube Hunter implies a late game value gameplan, while the name of Deathrattle Hunter implies a tempo aggro gameplan. Cube Hunter is a value deck for the most part. It does have to play like an aggro deck because of the lack of control tools in hunter. Cube Hunter is an imperfect deck.