Order of Use

The columns are the series in which the aliens originated, or categories in the case of Ultimate and Enhanced forms. The rows are for the series in which they appeared.
Series 	Original Series 	Alien Force 	Ultimate Alien 	Omniverse 	Reboot 	Ultimates 	Enhanced
Original Series	HeatblastWildmuttDiamondheadXLR8Grey MatterFour ArmsStinkflyRipjawsUpgradeGhostfreakCannonboltWildvineSpitterBuzzshockArctiguanaBlitzwulfSnare-OhFrankenstrikeUpchuckDittoEye GuyWay Big	N/A 	N/A 	N/A 	N/A 	N/A 	N/A
Alien Force 	CannonboltUpchuckWay BigDiamondheadGhostfreak 	SwampfireEcho-EchoHumungousaurJetrayBig ChillChromastoneBrainstormSpidermonkeyGoopAlien X 	N/A 	N/A 	N/A 	HumungousaurSwampfire 	N/A
Ultimate Alien 	WildmuttCannonboltUpchuckFour ArmsWay BigRipjawsHeatblastStinkflyDiamondheadArctiguanaXLR8GhostfreakUpgrade 	HumungousaurJetrayChromastoneSpidermonkeyRathEcho-EchoBig ChillLodestarSwampfireNanomechBrainstormGoopAlien X	Water HazardAmpFibianArmodrilloTerraspinNRGFasttrackChamAlienEatleClockworkShocksquatchJury Rigg	N/A 	N/A 	SpidermonkeyBig ChillHumungousaurCannonboltSwampfireEcho-EchoWildmuttBenWay Big	N/A
Omniverse 	Four ArmsCannonboltStinkflyHeatblastXLR8DiamondheadWildmuttGrey MatterArctiguanaWildvineRipjawsWay BigSnare-OhFrankenstrikeBuzzshockBlitzwulf 	LodestarSpidermonkeyChromastoneSwampfireNanomechEcho-EchoRathAlien XHumungousaurBig ChillGoopBrainstorm 	NRGWater HazardTerraspinArmodrilloShocksquatchClockworkAmpFibianJury RiggEatle 	FeedbackBloxxGravattackCrashhopperBall WeevilWalkatroutPesky DustMole-StacheThe WorstKickin HawkToepickAstrodactylBullfragAtomixGutrotWhampire	N/A 	HumungousaurSpidermonkeyEcho-EchoAlbedoArctiguanaGravattackRath 	N/A
Reboot 	CannonboltHeatblastXLR8Four ArmsGrey MatterDiamondheadUpgradeStinkflyWildvine 	RathHumungousaur 	N/A 	N/A 	OverflowGaxShock RockSlapback	N/A 	DiamondheadGrey MatterWildvineHeatblastFour ArmsCannonboltStinkflyOverflowXLR8