Lurking Roper, and Viridian Longbow

Prerequisites

• Lurking Roper on the battlefield
• Viridian Longbow on the battlefield
• Viridian Longbow attached to Lurking Roper
• Lurking Roper does not have summoning sickness
• You have a way to give Lurking Roper lifelink

Steps

1. Activate Lurking Roper by tapping it, dealing 1 damage to any target and causing you to gain one life
2. Lurking Roper triggers, untapping it
3. Repeat

Results

• Infinite damage
• Infinite lifegain
• Infinite lifegain triggers