Tapu Lele

Tapu Lele is one of the most versatile and devastating offensive forces in the Doubles OU metagame. This can mostly be owed to its ability, Psychic Surge, as it both provides invaluable support by blocking priority moves such as Fake Out for grounded teammates and provides a power boost to Psychic-type moves used by grounded Pokemon, heightening the power of Tapu Lele's Psychic-type blows to astronomical levels. With high natural offensive potential, STAB coverage that's walled only by Steel, just-enough Speed, workable bulk if invested into, and access to Taunt, Tapu Lele is highly customizable and can fulfill a bevy of roles, from a fast attacker that can crumble foes to a bulky pivot that can also keep threats in check with its respectable power. In particular, Tapu Lele is a very effective user of Taunt, as it can reliably stop any setup without fear of Fake Out thanks to the aforementioned Psychic Surge.

Still, Tapu Lele has to watch out for opposing Steel-types such as Mega Metagross, Aegislash, Celesteela, and Bronzong, as they can simply shrug off any blow from it and take advantage of its futile presence. In addition, Tapu Lele's bulk is average at best—its Defense paper thin in particular—and its Speed is only middling, leaving non-Choice Scarf sets prone to being beat down by faster threats in the metagame such as Mega Charizard Y, Mega Metagross, Mega Salamence.