yeah so I'm new to the uber metagame, I haven't really put much thought into this team but here it is.
@Choice Specs
Timid
252 SpA/216 Spe/40 HP
-Aura Sphere
-Ice Beam
-Shadow Ball
-Grass Knot
I'm not too sure about this lead, but it does a nice job of beating Darkrai and Groudon leads. I'm open to suggestions if anyone has ideas for a different lead. I've found Mewtwo in most battles to be the weakest link in my team.
@Choice Scarf
Modest
52 HP/252 SpA/204 Spe
-Dark Pulse
-Thunder
-Spacial Rend
-Focus Blast
My revenge killer. It catches quite a few scarf Palkia, scarf Kyogre, Deoxys, and Mewtwo by surprise. The speed EVs allow it to outrun max speed Deoxys-S.
@Soul Dew
Timid
112 HP/204 SpA/192 Spe
-Calm Mind
-Dragon Pulse
-Thunder/Grass Knot?
-Recover
Latias provides me with a safe switch into Kyogre. Without her, I would be swept pretty badly by scarfogre. Should I go with Grass Knot>Thunder since I got Groudon on my team?
@Life Orb
Adamant
116 HP/252 Atk/140 Spe
-Rock Polish
-Earthquake
-Stone Edge
-Dragon Claw
It seems to me that a lot of teams are unprepared for the threat that is Rock Polish Groudon. After 1 Rock Polish it outspeeds Jolly scarfchomp, and it gets perfect coverage with the 3 attacking moves. This also serves as my Dialga and Jirachi counter (I haven't seen a single Dialga with Magnet Rise yet).
@Choice Band
Adamant
252 HP/252 Atk/6 Spe
-Bullet Punch
-U-Turn
-Superpower
-Pursuit
A trapper/revenge killer of sorts. Bullet Punch lets it kill weakened sweepers such as Rayquaza and Darkrai, while Pursuit is great for predicted switches. You can't go wrong with U-Turn, it does a shitload to anything that doesn't resist it and gives an opportunity to switch into a counter. Superpower nails Registeel, and Dialga, it also does slightly more to Jirachi than U-Turn. Scizor isn't going to be outspeeding anything in ubers so I just dumped the remaining EVs into HP for more bulk.
@Choice Band
252 Atk/252 Spe/6 HP
Adamant
-ExtremeSpeed
-Ice Punch
-Fire Punch
-SuperPower/ThunderPunch?
Deoxys reaches a ridiculous 756 Atk with CB and noboy really expects it. Ice Punch OHKOs Latias who think they can stay in, and Fire Punch hits unsuspecting Forretress, Jirachi, and Metagross. ExtremeSpeed is useful for revenge killing faster stuff (it does around 75% to Rayquaza and Kyogre). I'm thinking I should drop Superpower for ThunderPunch, seeing how Ho-Oh weak my team is. SuperPower is only really good for maybe Dialga, but Groudon already counters it. Suggestions on superpower vs tpunch?

Timid
252 SpA/216 Spe/40 HP
-Aura Sphere
-Ice Beam
-Shadow Ball
-Grass Knot
I'm not too sure about this lead, but it does a nice job of beating Darkrai and Groudon leads. I'm open to suggestions if anyone has ideas for a different lead. I've found Mewtwo in most battles to be the weakest link in my team.

Modest
52 HP/252 SpA/204 Spe
-Dark Pulse
-Thunder
-Spacial Rend
-Focus Blast
My revenge killer. It catches quite a few scarf Palkia, scarf Kyogre, Deoxys, and Mewtwo by surprise. The speed EVs allow it to outrun max speed Deoxys-S.

Timid
112 HP/204 SpA/192 Spe
-Calm Mind
-Dragon Pulse
-Thunder/Grass Knot?
-Recover
Latias provides me with a safe switch into Kyogre. Without her, I would be swept pretty badly by scarfogre. Should I go with Grass Knot>Thunder since I got Groudon on my team?

Adamant
116 HP/252 Atk/140 Spe
-Rock Polish
-Earthquake
-Stone Edge
-Dragon Claw
It seems to me that a lot of teams are unprepared for the threat that is Rock Polish Groudon. After 1 Rock Polish it outspeeds Jolly scarfchomp, and it gets perfect coverage with the 3 attacking moves. This also serves as my Dialga and Jirachi counter (I haven't seen a single Dialga with Magnet Rise yet).

Adamant
252 HP/252 Atk/6 Spe
-Bullet Punch
-U-Turn
-Superpower
-Pursuit
A trapper/revenge killer of sorts. Bullet Punch lets it kill weakened sweepers such as Rayquaza and Darkrai, while Pursuit is great for predicted switches. You can't go wrong with U-Turn, it does a shitload to anything that doesn't resist it and gives an opportunity to switch into a counter. Superpower nails Registeel, and Dialga, it also does slightly more to Jirachi than U-Turn. Scizor isn't going to be outspeeding anything in ubers so I just dumped the remaining EVs into HP for more bulk.

252 Atk/252 Spe/6 HP
Adamant
-ExtremeSpeed
-Ice Punch
-Fire Punch
-SuperPower/ThunderPunch?
Deoxys reaches a ridiculous 756 Atk with CB and noboy really expects it. Ice Punch OHKOs Latias who think they can stay in, and Fire Punch hits unsuspecting Forretress, Jirachi, and Metagross. ExtremeSpeed is useful for revenge killing faster stuff (it does around 75% to Rayquaza and Kyogre). I'm thinking I should drop Superpower for ThunderPunch, seeing how Ho-Oh weak my team is. SuperPower is only really good for maybe Dialga, but Groudon already counters it. Suggestions on superpower vs tpunch?