Stalwart Successor, Grinding Station, and Lesser Masticore

Prerequisites

• Stalwart Successor on the battlefield
• Grinding Station on the battlefield
• Lesser Masticore on the battlefield

Steps

1. Activate Grinding Station by tapping it and sacrificing Lesser Masticore When Lesser Masticore dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
2. When Lesser Masticore enters, Grinding Station and Stalwart Successor trigger
3. Resolve the Grinding Station trigger, untapping it Resolve the Stalwart Successor trigger, putting a +1/+1 counter on Lesser Masticore Resolve the Grinding Station ability from step 1 Repeat

Results

• Infinite artifact ETB
• Infinite artifact LTB
• Infinite artifact sacrifice triggers
• Infinite creature ETB
• Infinite creature LTB
• Infinite death triggers
• Infinite mill
• Infinite creature sacrifice triggers
• Infinite self-mill