Xavier Sal, Infested Captain + Intruder Alarm + Staff of Titania + Prowling Felidar

Xavier Sal, Infested Captain

Intruder Alarm

Staff of Titania

Prowling Felidar

How it works

1. Activate Xavier Sal by tapping it and removing a counter from a permanent you control, creating a token copy of the Forest Dryad token.
2. When the Forest Dryad enters the battlefield, Intruder Alarm and Prowling Felidar trigger.
3. Resolve the Prowling Felidar trigger, putting a counter on a creature you control.
4. Resolve the Intruder Alarm trigger, untapping all creatures.
5. Repeat.

This loop relies on the brilliant synergy between land-based token creation and continuous untapping to generate an unstoppable engine. When you activate Xavier Sal, Infested Captain by spending a counter to populate a Forest Dryad—which you can easily equip with Staff of Titania to help generate your tokens or boost your board—that new Dryad enters the battlefield and triggers Prowling Felidar to grow larger with a +1/+1 counter. At the same time, Intruder Alarm catches that creature entry and untaps all your creatures, including Xavier Sal, Infested Captain. Because you removed a counter from Prowling Felidar to fuel the captain's ability in the first place, you can simply repeat this cycle infinitely, netting endless Forest Dryad tokens, landfall triggers, and untaps.