So lets start with Pikachu then.
Pikachu @ Light Ball
252 Atk/ 252 Spd/ 4 Sp. Atk
Realistically Pikachu is worth one good Volt Tackle and that's it. It takes a lot of work to keep this thing alive with that weak 35 HP. But everyone loves him, and so do I <3
Volt Tackle is the primary move for attacking. Brick Break is for steels and Tyranitar and things like that. Grass Knot is for ground types and Volt Switch is my STAB option on the special side that allows for scouting as well.
The first thing that came to mind when building this team around Pikachu is preventing hazards.
Mandibuzz @ Leftovers
248 HP/ 252 Def/ 8 Sp. Def
The bulkiest Defogger out there! This set is really standard. Roost for recovery. Defog to get rid of hazards, including mine sadly so I need to use this wisely. U-Turn can be used to maybe set up a VoltTurn with Pikachu lol, but Taunt stops her from being set up on. And Foul Play is her attacking option.
Initially I thought having Sand on this team would be bad for Pikachu, but..
4 Hp /252 Atk/ 252 Spd
I want Tyranitar to act as a set up sweeper on his own, this way he doesn't hurt Pikachu all that much. When I have switch advantage I can send him out and try setting up a sweep. Dragon Dance is the set up move of choice. Crunch is the primary STAB. Stone Edge is another STAB. And Iron Head could be for fairies, but Pursuit goes better with the role this Tyranitar has. When I have switch advantage against a Latios or something I can easily revenge kill, and without Pursuit Id miss an easy OHKO.
And now that this team has Sand on it, more hazard prevention!
Excadrill @ Air Balloon
4 HP/ 252 Atk/ 252 Spd
This is another Typical Set. Rapid Spin gets rid of hazards. Earthquake is STAB. Iron Head is STAB. Rock Slide is for flying types.
I also need sticky web support.
Smeargle @ Focus Sash
252 HP/ 252 Spd/ 4 Def
Sticky Web is to slow things down for the entire team including Pikachu. Spore
is to put everything that isnt a grass type to sleep. Stealth Rock is my other hazard of choice and Destiny Bond can catch people off guard if I know I'm about to receive my last fatal blow.
And unfortunately I can't get any legendaries from previous games. Heatran and Jirachi would be perfect for this team!
I have to settle for the Celebi I got from Pokebank.
Celebi @ Leftovers
252 HP/ 252 Sp. Def/ 4 Sp. Atk
Docile(Only nature I can get, he has outstanding IVs though)
Recover is the best healing option I have. ****Psychic** is a good STAB. T-Wave/Toxic are the best two statuses available. U-Turn can be used for scouting. Energy Ball is another STAB.
I kinda just built this team on the fly, but tell me what you think!