Halloween costume ideas

I'm planning to write a one-shot about the various misadventures that Ash, Kari and Brock have while trick-or-treating one Halloween, and as such need costume ideas.

My initial plan was to have Ash be Link (so Pikachu could be Navi), Kari be Sailor Mars (both look similar in build and hairstyle) and Brock be a Final Fantasy style warrior (based on the warrior from Final Fantasy Dawn of Souls)

If you have any other suggestions for anime or game characters they could be, tell me! (for Ash's suggestions, include something Pikachu could be too)

I have an idea for Ash and Pikachu. Ash could be Fuyuki and Pikachu could be Sgt. Keroro. Both of them are from SGT. Frog manga. Brock could be Miroku from Inuyasha, since they both act a lot alike. And Kari could be either Kagome from Inuyasha, or Tohru from Fruits Basket.

I hope you like them ^^