Expansion // Explosion + Twincast
Produces: Infinite magecraft triggers
- Color identity
- UR
- Mana
- {U}{U}{U/R}{U/R}, plus enough mana to cast the additional spell if needed
Prerequisites
You have a way to cast an additional instant or sorcery, or an opponent is casting one.
Steps
- Cast any other instant and/or sorcery spell, or wait for an opponent to cast one.
- Holding priority, cast Expansion by paying {U/R}{U/R}, copying the next instant or sorcery spell you cast with mana value four or less.
- Cast Twincast by paying {U}{U}, targeting the instant or sorcery spell cast in step 1.
- The delayed trigger from Expansion triggers, copying Twincast, with the copy targeting the original Twincast.
- Resolve the copy of Twincast, copying Twincast, with the copy targeting the original Twincast.
- Repeat step 5.
How to execute this combo
The "Expansion // Explosion + Twincast" combo takes 6 steps in order. Make sure you have the mana open and permanents listed in the prerequisites before you start — opponents can respond between steps.
The end result: Infinite magecraft triggers.
Practice the line offline: lay out the cards, walk through each step, and note where you can lose the combo (summoning sickness, lack of priority, removal on a key permanent). In game, announce each step clearly; in casual play you can offer to shortcut after demonstrating the loop.
The best window is a turn when opponents are tapped out or after they commit a spell — hold protection (a counter, Vexing Shusher) if the combo wins on the spot.