Xavier Sal, Infested Captain + Intruder Alarm + Arlinn, Voice of the Pack

Xavier Sal, Infested Captain

Intruder Alarm

Arlinn, Voice of the Pack

How it works

1. Activate Arlinn's loyalty ability by removing two loyalty counters from it, creating a 2/2 Wolf creature token that enters the battlefield with a +1/+1 counter on it.
2. Activate Xavier Sal's first ability by tapping it and removing the +1/+1 counter from the Wolf token, creating a copy of the Wolf token that enters the battlefield with a +1/+1 counter on it due to Arlinn.
3. When the Wolf token enters the battlefield, Intruder Alarm triggers, untapping all creatures.
4. Repeat from step 2.

This loop turns your token maker into an infinite engine by exploiting the constant untapping power of Intruder Alarm. You start by using Arlinn, Voice of the Pack to generate a Wolf token, whose entry is supercharged by her static ability so it arrives with a +1/+1 counter already in place. Xavier Sal, Infested Captain then taps to consume that counter, triggering a populate effect that births a fresh copy of the token—which once again triggers Arlinn's passive +1/+1 counter bonus upon arrival. Every time that new token enters the battlefield, Intruder Alarm untaps Xavier Sal alongside your entire board, allowing you to repeat the process indefinitely for an unbounded army.