So first off, good luck in your first tourney. I hate to be the bearer of bad news, but I don't know that the strategy will be as effective in a competitive setting as you'd hope.
The biggest issue with the formidable mechanic is that it requires you to have a sizable board presence before it does anything. The problem here is that it will force you to over-extend into board wipes almost every game (that you would encounter them). Against most other decks, I just don't see it providing enough of an advantage to really get you there.
Further, however unfortunate, the only card with a formidable that you REALLY want is Surrak. I could maybe see 2x Stampeding Elk Herd to help break board stalls with Surrak out there or 2x Atarka Pummeler to again help break board stalls, but otherwise, I'm just not seeing enough payoff for the deck to really get there.
All that being said, if I were to suggest some changes to the existing deck, they would be as follows:
- You NEED 4x Elvish Mystic in this deck to help accelerate you. Sure, you have a few mana producers, but realistically, you aren't hitting any until T3 or later and you really don't need to ramp from 4-6, but from 3-4. A T1 Mystic lets you play so much more of your deck on T3 - even if you open with a tap-land.
- Qal Sisma Behemoth strikes me as being worth a look. Sure, the cost for attacking or blocking sucks, but realistically, it lets you hit formidable VERY fast. It's also a cheap 5/5. If you have a Mystic on the field, odds are he's not attacking, but he can definitely help pay for the behemoth.
- Shaman of the Great Hunt will literally make the deck sing. Either growing your dudes OR the sudden card draw can really make all the difference.
- Boon Satyr is an under-appreciated card that you can play in the opponent's end step. T1 mystic, t2 boon, t3 Surrak would be pretty hard to come back from.
- Temur Sabertooth is an almost must have for the board against control decks. It gives you some added resilience against their bevvy of removal and can save a lot of your creatures with its bounce ability.
- In a similar vein, Whisperwood Elemental is a card that would be well suited in any R/G mid-range deck. If you want to drop the cash for them, go for it as they're likely going to remain a staple for as long as they're legal in standard. If not, they're certainly not necessary, but they definitely would help.
- You're going to want some added removal or means to interact with the opponent's board. Whether that comes in the form of Lightning Strike, Wild Slash, or just Crater's Claws, you'll want SOME way to interact with their board.
I wish you the best of luck and I'm sure you'll be able to steal a few games here or there, but against top tier decks, I just don't see it getting there. Hopefully some of these comments will be of assistance as you continue to refine your build.
Good luck!
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