Requires

Steps

1. Activate Phyrexian Altar by sacrificing Geralf's Mindcrusher, adding .
2. When Geralf's Mindcrusher dies, its undying ability and Goldberry trigger.
3. Resolve the Geralf's Mindcrusher trigger, returning it from your graveyard to the battlefield with a +1/+1 counter on it.
4. When Geralf's Mindcrusher enters the battlefield, it and Intruder Alarm triggers.
5. Resolve the Geralf's Mindcrusher trigger, causing a player to mill five cards.
6. Resolve the Intruder Alarm trigger, untapping all creatures.
7. Holding priority, activate Goldberry's first ability by tapping it, moving the +1/+1 counter from Geralf's Mindcrusher onto Goldberry.
8. Resolve the Goldberry trigger from step 2, untapping it.
9. Activate Goldberry's second ability by paying and tapping it, moving the +1/+1 counter from Goldberry onto any permanent except Geralf's Mindcrusher, and causing you to draw a card.
10. Repeat.

Results