Fittest control LEGACY

I don't really see how orim's chant is especially powerful in this deck. Also, you really don't need the squadron hawks. If you survival all of your vengevines into your graveyard, it really should only take one attack for victory. Squadron hawk is really only useful if you plan on a stretched out game where your vengevines get killed a lot. This is probably not the case. Another thing you might want to watch out for is the graveyard hate that most legacy decks pack now because survival of the fittest is taking up a relatively large percentage of the metagame.

Orim's chant is mostly useful for protecting a win on turns where a deck will win rapidly, but also sometimes sees play on a stick to annoy your opponents until they draw a krosan grip. Survival will often win over multiple turns (eg dump vengevines one turn, get in for dmg turn afterwards). Orim's chant doesn't actually disrupt an opponent's hand or stop an answer from happening; it merely stalls. This can be incredibly effective in storm based combo decks, but I do not think it will prove to be as reliable in survival.
Another thing you might be concerned about is the small amounts of disruption you are running. You are running 8 free counterspells, but that is it. You may consider increasing that amount or packing some other form of disruption. If you were to cut your squadron hawks and orim's chants for cards that had an impact on the game state, I believe you would see much better performance out of this deck.