Crackleburr, and Song of Freyalise

Prerequisites

• Crackleburr on the battlefield
• Song of Freyalise on the battlefield
• You control at least two other blue creatures that do not have summoning sickness
• Crackleburr does not have summoning sickness
• Song of Freyalise has one or two lore counters on it

Steps

1. Activate Crackleburr and two other blue creatures you control by tapping them, adding
2. Activate Crackleburr's second ability by paying and untapping it and the two blue creatures, targeting any creature
3. Repeat

Results

• Infinite colored mana
• Return any number of creatures to their owner's hand