Hardened Berserker

The cost reduction here is shaped to chain. Attack, and the next spell you cast that turn comes down a generic mana cheaper, which puts the discount at its best when there's a second play waiting behind combat: another creature onto the board, a burn spell aimed at the blocker, a pump effect that turns a trade into a kill. The 3/2 body is built to die, not to dominate, so the reduction is the real payload, and it only fires when the card does the dangerous thing aggressive red wants anyway: turning sideways into open mana. The friction is timing. The trigger happens on the declaration of the attack, before blocks, so you commit to the swing and the follow-up with imperfect information, and the discount evaporates if you have nothing worth casting that turn. It rewards a hand stocked with cheap follow-ups and punishes a topdeck war. As a piece of aggressive-deck engineering, it belongs to a small line of attackers that subsidize the rest of the turn rather than just hitting for damage: the creature is a payment plan, spending its fragile body to make everything after it land a little harder.