Valor's Reach
Planes live in the awkward space between a game mode and a card, and this one commits fully to Planechase's combat-arena setting by rewarding a very specific attack pattern: send exactly two creatures, and the pair strikes twice. The number two is the whole constraint. Attack with one and nothing happens; attack with three and the trigger goes dark. It asks the team to thread a narrow lane between pressure and overcommitment, turning a decision usually about swinging wide into a decision about swinging precisely. The chaos ability then layers a second combat structure on top: untapping two attackers, then bolting an extra combat and main phase onto the turn if you rolled it during a main phase. That second combat is what elevates the double-strike clause past novelty, because the untap lets the same two creatures reload and cash the doubling bonus a second time in one turn. It is a design that thinks in phases rather than in stats, using the planar die's randomness to hand the active team extra turns-within-a-turn instead of extra cards or mana. The reward stays with whoever triggered chaos: the additional combat is added to the current turn, so only the active team gets to attack in it, and "your team" scopes the double-strike bonus to that player's side rather than the whole arena. The plane hands its widened phase structure to the team already holding initiative, letting a precise two-creature swing snowball into a compressed alpha strike.
