Zirda, the Dawnwaker + Iceberg + Doubling Season

Zirda, the Dawnwaker

Iceberg

Doubling Season

How it works

1. Activate Iceberg's first ability by paying 1, putting two ice counters on it.
2. Activate Iceberg's second ability by removing an ice counter from it, adding 1.
3. Repeat.

This clever setup hinges on a clever cost-reduction interaction with Iceberg's ice counters. Normally, paying {3} to put an ice counter on Iceberg would be cost-prohibitive, but Zirda, the Dawnwaker steps in to slash that activation cost down to just {1}. Meanwhile, Doubling Season quietly doubles any counters placed on permanents, meaning every single activated ability dumps two ice counters onto Iceberg instead of one for that same single mana. You can then repeatedly strip those counters off for colorless mana at a net profit, turning a curious old enchantment into an infinite mana engine.