Champion of Rhonas seems good to me, and there are many other ways in the format to cast spells without paying for them. This deck is an attempt to explore whether that can be leveraged enough.
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2 of these to swing for the fences and net 12-15 mana (if cast for free).
2 of these to provide a threat and cantrip card draw.
3 of these are in to cast 6-7 mana sorceries or devastating combat tricks.
4 of these is an attempt to get 5-10 free mana at some point in the game.
1 of Djeru: if I'm not spending mana on creatures or sorceries, I will have more for planeswalkers.
3 of to get free combats out of a modest team.
2 of these seems close enough to a combat trick to be beneficial.
2 of, seems a great finisher and a tremendous combo with Mirrorwing Dragon
1 of these although I'm not going for zombies as it is a hit for Hazoret's Undying Fury and it will enable me to cast almost anything in the deck.
1 of to re-use creatures felled in combat
2 of these to thin out for Hazoret's Undying Fury hits and stabilize versus aggro.
1 of to tilt combat in my favor
4 of these will surely be useful thoughout the game, particularly with Mirrorwing Dragon in play.
1 of these to marginally increase the value of Champion of Rhonas, Wildfire Eternal, and the fatty brigade when hard-cast.
4 of these will sometimes help me get to 4 mana on turn 3 without being swiftly removed, and stick around to finish up with Ridgescale Tusker, Slip Through Space and so on.
1 for card draw in the late game
24 lands: 18 green, 13 red, 6 white
3 Game Trail
2 Canopy Vista
2 Scattered Groves
2 Cinder Glade
2 Sheltered Thicket
1 Needle Spires
1 Evolving Wilds
6 Forest
1 Plains
4 Mountain
sideboard
Maybeboard