Not to discourage, but I am naturally critical. It's all in good jest, though:
1. Grow devourers with SoP while wardens killing enemy creatures
Wardens don't kill: dragons, scarabs, psions and a bunch of other airbornes. The general idea (SoP + Iridium Warden) seems fun, though.
2. Devourers should be burrowed while grown. Unborrwing will double the damage they can deal.
I think you mean 'grow
in
g'; also, fun interaction (burrow - growth - unburrow) -> seems unfair logical-wise, though (untargetable but still growing? pshaw)
3. Remove SoP and unburrow devourers when they are grown enough to end enemy in 2~3 turns
Although in theory this sounds as a solid plan, I see this not working out the way you intend. For instance, I foresee you running into the following problems:
1) Poison and/or weapons that kill you long before you are in killing range. This also concerns opponents who have (multiple) lifegain in play allowing them to heal for 20 a turn. In short, it might take a while before they are in 2~3 turns kill range.
2) You running out of cards since your plan is to stall with only three SoP back-up; it looks as if you would often just sit there with Wardens and Devourers and nothing else going on.
3) Of course each deck has it's strengths and weaknesses, but I fear this specific build loses to rush as well as to dedicated control. This is not even taking into account further advantages the AI has in Arena (double card-draw, increased mark, higher HP).
4. Steal shields before this last blow. Early stiletto is necessary against bonewalls.
I fear you might run out of Steals if you absolutely need them to get damage through in the end. This will not be the case against all opponents in Bronze as many don't use shields or weapons, but against the players where it does matter you might find you need to use two or three Steals only to stay alive.

All in all though, I like the theme and I have not encountered it often. If you have done some more playtesting I would be curious to see what your own conclusions are about this current build and how any deck updates might look.
Finally, on a personal note, I doubt what the market is for Bronze farmers that include 3 SoP, one of which is upped
