Worldwalker Helm, Treebeard, Gracious Host, Scurry Oak, and Teething Wurmlet

Prerequisites

• Worldwalker Helm on the battlefield
• Treebeard, Gracious Host in hand or on the battlefield
• Scurry Oak on the battlefield
• Teething Wurmlet on the battlefield
• You have a way to gain any amount of life

Steps

1. Gain any amount of life
2. Treebeard triggers, putting a +1/+1 counter on Scurry Oak
3. Scurry Oak triggers, creating a 1/1 Squirrel creature token and a Map artifact token
4. When the Map enters the battlefield, Teething Wurmlet triggers, causing you to gain 1 life
5. Repeat from step 2

Results

• Infinite +1/+1 counters on Scurry Oak
• Infinite creature tokens
• Infinite ETB
• Infinite lifegain
• Infinite lifegain triggers
• Infinite Map tokens