Regieleki

While Regieleki is mostly a terrible Pokemon in DOU, it does have an incredibly minor niche as a workable hyper offense attacker alongisde Tapu Koko. Boasting a blazing base 200 Speed that lets it outrun even Kingdra under rain and Choice Scarf users such as Urshifu-R and Genesect, Regieleki blitzes through opposing offensive teams if enabled with Electric Terrain, as Regieleki's Transistor-boosted STAB attacks become quite lethal even to bulky and resistant foes, with Rising Voltage able to OHKO Incineroar, Dragapult, Mew, and Naganadel. The problem, of course, is how Regieleki is easily checked defensively as it has absolutely no usable coverage moves, leaving it easily answered by Zeraora, Ground-types, such as Zygarde and Landorus, and the metagame's bulky Grass- and Dragon-types, such as Rillaboom, Ferrothorn, Amoonguss, and Kyurem-B. Urshifu-R and Kyurem-B are thus solid partners, as they can each cover some of these threats while also being strong attackers in line with Regieleki's aggressive playstyle. Still, the pairing with Tapu Koko is optimistic at best, because Tapu Koko is generally also a suboptimal pick in the DOU metagame, and other Terrain setters are quite omnipresent, especially with a top DOU Pokemon in Rillaboom being a particularly hard counter. Regieleki is ultimately often dead weight, its high Speed invalidated and frailty exposed by the prevalence of Fake Out and priority moves, speed control such as Tailwind and Trick Room, and its own inability to threaten anything with a non-Electric-type attack.