Incubation Druid, Umbral Mantle, and Leyline of Abundance

Prerequisites

• Incubation Druid on the battlefield
• Umbral Mantle on the battlefield
• Leyline of Abundance on the battlefield
• Umbral Mantle attached to Incubation Druid
• Incubation Druid does not have summoning sickness
• Incubation Druid has at least one +1/+1 counter on it

Steps

1. Activate Incubation Druid's first ability by tapping it, adding three mana of any color a land you control could produce
2. Leyline of Abundance triggers, adding
3. Activate Incubation Druid by paying and untapping it, giving itself +2/+2 until end of turn
4. Repeat
5. Once you have infinite , you may activate Leyline of Abundance's ability to put infinite +1/+1 counters on each creature you control

Results

• Infinite +1/+1 counters
• Infinitely large Incubation Druid until end of turn
• Infinite mana lands you control can produce