At 10 mana you get 3 4/5's, equalling 12/15 stats total. This could actually be pretty powerful in a zoo type deck or in any warlock deck for the late game. Most likely meant for arena though. It also makes druids possibly reconsider using biology project because of their opponent possibly using this quicker than anticipated. I say this is a decent card that might see some play, depending on more cards and the meta of course
This with Brann Bronzebeard for a huge pile of stats or together with Loatheb for some aoe protection or if you manage to discount all three of them with Emperor Thaurissan, then you will get a huge pile of stats + total aoe protection....
dropping this and Loatheb on turn 10 is pretty scary
You already have warlock DK and Nzoth, I can't see this being played much in wild when the meta is mostly aggro and you already have enough late game. Maybe sees play as a 1 of in standard since Nzoth is wild only and way better.
Realistically, even if you managed to survive till turn 10, could you survive playing a bunch of minions that do nothing and don't have taunt? Even N'Zoth was only played if he ressed a wall of taunts. And his effect was much more powerful.