Lullmage Mentor + Anointed Procession + Doubling Season + Elspeth, Storm Slayer

Lullmage Mentor

Anointed Procession

Doubling Season

Elspeth, Storm Slayer

How it works

1. Whenever an opponent casts a spell, activate Lullmage Mentor by tapping seven untapped Merfolk, countering that spell.
2. Lullmage Mentor triggers, creating a total of eight 1/1 Merfolk creature tokens.
3. Repeat.

This brilliant token-multiplying engine starts when you activate Lullmage Mentor's counter ability by tapping seven untapped Merfolk, which successfully counters an opponent's spell. That very counter event triggers Lullmage Mentor's first ability to create a 1/1 Merfolk token, but your board is completely transformed because Anointed Procession, Doubling Season, and Elspeth, Storm Slayer all feature replacement effects that exponentially stack together to turn that single token into a massive squad of eight. With those new Merfolk ready to tap, you can repeat the loop to completely lock opponents out of casting spells while generating a boundless army of creatures.