Dross Scorpion + Elemental Mastery + Altar of Dementia + Biotransference

Dross Scorpion

Elemental Mastery

Altar of Dementia

Biotransference

How it works

1. Activate the creature with Elemental Mastery attached by tapping it, creating a number of 1/1 Elemental creature tokens with haste equal to its power.
2. Activate Altar of Dementia by sacrificing an Elemental.
3. When the Elemental dies as an artifact due to Biotransference, Dross Scorpion triggers, untapping the creature with Elemental Mastery attached.
4. Resolve the Altar of Dementia ability.
5. Repeat.

This ingenious loop transforms raw creature power into an unstoppable mill engine by turning every token you create into a mechanical stepping stone. While Altar of Dementia converts your creatures into milled cards and Dross Scorpion provides the untap trigger whenever an artifact dies, Biotransference does the crucial heavy lifting of making all your creatures into artifacts so the Scorpion can actually see them hit the graveyard. With Biotransference setting the stage, you enchant your heaviest-hitting creature with Elemental Mastery to tap for a flood of hasty tokens, which you immediately sacrifice to the Altar; each death triggers Dross Scorpion to untap your mastery-enchanted powerhouse, letting you repeat the entire process indefinitely until your opponents' libraries vanish entirely.