Gilder Bairn + Cryptolith Rite + Biomancer's Familiar

Gilder Bairn

Cryptolith Rite

Biomancer's Familiar

How it works

1. Activate Gilder Bairn by tapping it, adding G/U.
2. Activate Gilder Bairn by paying G/U and untapping it, doubling each counter on target permanent.
3. Repeat.

This delightful engine turns Gilder Bairn into an exponential counter-doubling machine, thanks to the cost-reduction power of Biomancer's Familiar and the mana-producing gift of Cryptolith Rite. With Biomancer's Familiar on the board, Gilder Bairn's untap ability becomes cheap enough to fund itself with the mana generated from tapping via Cryptolith Rite's granting of the tap-for-mana ability. Each iteration taps Gilder Bairn to pay for its own activation while simultaneously untapping to double every counter on a chosen permanent, resulting in infinite growth.