Myr Welder + Biotransference + Empowered Autogenerator + Merrow Grimeblotter

Myr Welder

Biotransference

Empowered Autogenerator

Merrow Grimeblotter

How it works

1. Activate Myr Welder using Empowered Autogenerator's ability by tapping it, putting a charge counter on Myr Welder and adding or for each charge counter on Myr Welder.
2. Activate Myr Welder using Merrow Grimeblotter's ability by paying 1U/B and untapping it, giving target creature -2/-0 until end of turn.
3. Repeat.

This ingenious contraption centers on Myr Welder absorbing the activated abilities of Empowered Autogenerator and Merrow Grimeblotter once those artifacts are safely in the graveyard. Biotransference plays a crucial foundational role here by turning Myr Welder—and all creature cards you own not on the battlefield—into artifacts, ensuring the welder can legally imprint artifact cards and even benefit from its own mechanical classification. Once the setup is complete, you tap the creature to grow its charge counters and generate a massive surge of mana via Empowered Autogenerator's stolen ability, then filter a portion of that energy right back into Merrow Grimeblotter's untap cost to repeat the loop endlessly.