Aether Membrane

A flier crashes into the 0/5, the attacker deals its combat damage as normal, and only at end of combat does the attacker get sent back to its owner's hand: no card lost, but a tempo cycle wasted, the same threat needing to be recast and re-thrown into the same wall next turn. That bounce-on-block clause borrows from blue's defensive grammar, the color that walls up and resets attacks, and grafts it onto a red body that ordinarily wants to swing and punish blockers. Reach extends the body's reach to the air war, letting a 0/5 answer the evasive threats it would otherwise wave past. The return is non-negotiable and untargeted: it fires whenever the wall blocks a creature, not at your choosing, so it taxes the opponent's tempo automatically rather than functioning as removal. Because the bounce resolves after the combat damage step, attack triggers have already resolved and damage has already been dealt; what it denies is not this swing's payoff but the attacker's continued board presence, forcing a fresh commitment of mana and a turn to put it back in play. As an off-color experiment it reads as a question about how much of blue's stall-and-reset toolkit red can hold without losing its own identity: no flying of its own, no card advantage, just a sturdy body that buys time one swing at a time.