Ultraman: Matching you with an equally matched daddy

Takahashi, transported to the world of Ultraman Tiga, acquired a cheat code supposedly granting him absolute fairness in competition: the ability to transform into any Ultraman. But why is his opponent the S++ level Eternal Shining Gatanothor, while his transformed Ultraman is the S-- Shining Tiga?! Is this the fairest ELO matchmaking system in history? Every transformation, this lousy system draws the weakest Ultraman for Takahashi. In every battle, his enemies are strengthened by Sphia and other strange characters. His teammates are all heavyweights: the battered and bruised Tiga, Dyna corrupted by Sphia and prone to berserk rages, the godlike Seven who doesn't love anyone, and Leo, wallowing in grief over the loss of his homeland. And every now and then, even more enemies invade this already insanely difficult world. Root Destruction Entity, Demon King Beast, Chaos Head, Negative Energy Monster… Greeza, Emperor, Reiblood Alien, Zagi… Fortunately, the original human hosts of these worlds will also arrive in this world. Gaia, attempting to destroy humanity; Cosmos, resolutely upholding justice; Max, actively intervening in humanity's dark side; Mebius, donning the armor of vengeance; Nexus, cowardly and afraid of death… Why are my teammates either crippled or incompetent? The only reliable teammate is the GUTS's little plane. In short, one god carrying four noobs, every match is a peak performance, and any mistake leads to a disastrous end. Takahashi declares, "Merging the Great World, don't come if you're a cheater!" This book is also known as "Ultraman: Matching You with an Equally Powerful Daddy."