High Alert Combos
Axebane Guardian + High Alert
Bloom Tender + High Alert
Faeburrow Elder + High Alert
Kami of Whispered Hopes + High Alert
Sanctum Weaver + High Alert
Selvala, Heart of the Wilds + High Alert
Codie, Vociferous Codex + High Alert + Agatha of the Vile Cauldron
Codie, Vociferous Codex + High Alert + Opalescence
Codie, Vociferous Codex + High Alert + Zirda, the Dawnwaker
High Alert + Angelic Protector + Lightning Greaves
High Alert + Task Force + Lightning Greaves
Jegantha, the Wellspring + High Alert + Zirda, the Dawnwaker
Combo result
Infinite black mana that cannot be spent to pay generic mana costs. Infinite red mana that cannot be spent to pay generic mana costs. Infinite green mana that cannot be spent to pay generic mana costs.
Prerequisites
All permanents on the battlefield. Jegantha does not have summoning sickness.