Agatha's Soul Cauldron, Lurking Roper, and Traveling Minister

Prerequisites

• Agatha's Soul Cauldron on the battlefield
• Lurking Roper on the battlefield
• Traveling Minister in exile

Steps

1. Activate Lurking Roper using Traveling Minister's ability by tapping it, causing target creature to get +1/+0 until end of turn, and you to gain 1 life
2. Lurking Roper triggers, untapping itself
3. Repeat

Results

• Infinite lifegain
• Infinite lifegain triggers
• Infinite power for creatures you control until end of turn