Tales of Symphonia/EX Skills

Ex Skills are skills that can be equipped to all playable characters via Ex Gems. There are four levels of Ex Skills, each corresponding to a certain-leveled Ex Gem. And, each level has four available skills. Once an Ex Gem has been equipped, you can't take it off. You can replace it with another gem, but the previously equipped one will be lost.

Each Ex Gem is also aligned with "Tech" or "Strike" and will make the character equipping them disposed to that side.