Sisay, Weatherlight Captain, Jegantha, the Wellspring, and Intruder Alarm

Prerequisites

• Sisay, Weatherlight Captain on the battlefield
• Jegantha, the Wellspring on the battlefield
• Intruder Alarm on the battlefield
• Jegantha does not have summoning sickness

Steps

1. Activate Jegantha by tapping it, adding that cannot be spent to pay generic mana costs
2. Activate Sisay by paying , searching your library for a legendary creature card with mana value less than Sisay's power and putting it onto the battlefield
3. When the legendary creature enters the battlefield, Intruder Alarm triggers, untapping all creatures
4. Repeat

Results

• Put all legendary creatures with mana value less than Sisay's power from your library onto the battlefield