23 cards where the colors ≥ BGR and the block is “ala”

Broodmate Dragon (ALA)
Carrion Thrash (ALA)
Charnelhoard Wurm (CON)
Child of Alara (CON)
Conflux (CON)
Dragon Appeasement (ARB)
Fusion Elemental (CON)
Giant Ambush Beetle (ARB)
Hellkite Overlord (ALA)
Jund Charm (ALA)
Jund Hackblade (ARB)
Jund Sojourners (ARB)
Karrthus, Tyrant of Jund (ARB)
Kresh the Bloodbraided (ALA)
Lavalanche (ARB)
Madrush Cyclops (ARB)
Maelstrom Archangel (CON)
Maelstrom Nexus (ARB)
Progenitus (CON)
Sangrite Backlash (ARB)
Scarland Thrinax (CON)
Sprouting Thrinax (ALA)
Violent Ultimatum (ALA)

This search is finished. Now the real work can begin.