If you want to be more offensive, you might want to change Empoleon for a faster water type like Starmie
Also, if you plan to take out the Giratina cause of it being an uber I'd say to get Salamence if you want a dragon or Gengar if you want a ghost

...DON'T BRING IN SMOGON TIERS WHEN SOMEBODY IS TALKING ABOUT REGULAR GAMEPLAY

Well, a lot of people would think using legendaries, which is what I should have said, to beat the game is an easy way out

Girantina is slightly more defensive than offensive until it is given a Griseous Orb, so it is sort of an exception

He's using the Origin Forme, here's the normal one

Just because they show the Origin Forme sprite doesn't mean that it's the forme they're using