Koola
Koola can transform like his brother Frieza, but he can only do so one time. At the power level of 40,000,000 Koola can assume his second stage, this will increase his power level by 275% and his Attack Damage and Hit Points by 75%.
Garlic Jr. and the Spice Boys
Garlic Jr. and his minions the Spice Boys have the ability to transform into large more powerful versions of themselves. This can be done at a natural power level of 25,000,000. This will increase their power level 100% and their Attack Damage and Hit Points by 50%. This Transformation also applies to Bojack and his henchmen.
Zarbon
Zarbon can pump himself up into his Monster Form from the start...what this does is increases all his stats by 10%.