When Tersa Lightshatter enters, discard up to two cards, then draw that many cards.
Whenever Tersa Lightshatter attacks, if there are seven or more cards in your graveyard, exile a card at random from your graveyard. You may play that card this turn.
Tersa wants to fill the graveyard fast, then attack to exile and cast free cards off the top of your bin every turn. You loot on every recast, churn through your deck, and grind incremental card advantage that mono-red usually lacks. Build a wide, aggressive curve plus impulse/graveyard payoffs and convert that velocity into a flood of cheap threats and burn.
Repeatable card advantage and looting in a color starved for it
Cheap, hasty body that pressures immediately and protects itself by attacking
Synergizes with discard outlets, madness, and graveyard recursion
Easy to recast and rebuild around at only three mana
Random exile means inconsistent and sometimes useless hits
Mono-red lacks strong interaction and ramp
Reliant on connecting in combat, so good blockers and removal slow it down
Graveyard hate can shut off the attack trigger entirely
Filters dead cards into gas while feeding the bin for the attack trigger.
Add fast mana like Jeweled Lotus, Mana Crypt, and ritual effects to enable big Breach turns, plus more reliable discard outlets and cheap recursion to guarantee the seven-card threshold. Lean into a tight, low curve so random graveyard hits are almost always castable, and include free interaction like Pyroblast and Deflecting Swat to protect your engine.