darkSpyro

This may have been asked before, but a lot of series 1 characters have caught my eye, and I need some clarification before I buy any. If I use a series 1 skylander, for example Stealth Elf, on a newer game such as Trap Team, would I be able to buy her soul gem ability without having to find it in Spyro's Adventure?

Yes, you only need to find the Soul Gem in the game the character was released. In the next game(s), the ability is available to purchase by default.