Berta, Wise Extrapolator, Agatha's Soul Cauldron, Farmstead Gleaner, and Mikaeus, the Lunarch

Prerequisites

• Berta, Wise Extrapolator on the battlefield
• Agatha's Soul Cauldron on the battlefield
• Farmstead Gleaner in exile
• Mikaeus, the Lunarch in exile
• available

Steps

1. Activate Berta using Mikaeus's first activated ability by tapping them, putting a +1/+1 counter on Berta
2. Berta's second ability triggers, adding one mana of any color
3. Activate Berta using Farmstead Gleaner's ability by paying and untapping them, putting a +1/+1 counter on Berta
4. Berta's second ability triggers, adding one mana of any color
5. Repeat any number of times
6. Once you have infinite +1/+1 counters on Berta, you may repeat the loop using Mikaeus's last activated ability in step 1 instead, putting infinite +1/+1 counters onto creatures you control

Results

• Infinite +1/+1 counters on creatures you control