Xavier Sal, Infested Captain + Intruder Alarm + Staff of Titania + Territorial Scythecat

Xavier Sal, Infested Captain

Intruder Alarm

Staff of Titania

Territorial Scythecat

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 Territorial Scythecat trigger.
3. Resolve the Territorial Scythecat trigger, putting a counter on a creature you control.
4. Resolve the Intruder Alarm trigger, untapping all creatures.
5. Repeat.

This clever loop turns the humble Forest Dryad token from Staff of Titania into an engine for infinite growth and untaps. Every time the Dryad enters the battlefield, Territorial Scythecat grows larger from the landfall trigger while Intruder Alarm untaps your entire board in response. This freshly untapable Xavier Sal, Infested Captain can then tap to sacrifice a creature and proliferate your growing board, or remove a counter to populate another Forest Dryad, keeping the entire cascade spinning endlessly.