Well, I'd take out the black critter, and go mostly GW, light on black. Cut
Unyielding Krumar,
Archers' Parapet, and
Debilitating Injury, play
War Behemoth,
Tusked Colossodon, and
Roar of Challenge. I haven't really put it together, but I'd go 7/7/5, maybe 8/7/4 GWB sources, with that. No banner, assuming this is draft. I'd also expect to lose two games to mana, but still, I might not, and I would surely lose without the Ascendancy and the Charm. I would not go below 15 critters, but I might lose
Incremental Growth for 18th land, for consistency. In fact, this build has almost no two-drops, so 18 mana is probably very much indicated.