[Plant42]

Originally Posted by kuroishinigami

The esper side is becoming more and more like heroes series lol. Wonder if there will be an esper that could copy other esper's ability or one that can manipulate time next ^^. that Mental Out is explained in SS2 too right? I gotta look for it ^^

BTW, what's a gemstone? Is it some kind of ability?

Actually there is one
From Wiki:

Rikou Takitsubo
Member of ITEM. She suffers from brain damage after fighting and being defeated by Teitoku Kakine; as a result, she can no longer use her esper abilities. Her ability was the AIM Stalker (能力追跡, Nouryoku Tsuiseki?, "ability tracker") which she uses to track down the esper. She also states that her ability allowed her to steal other esper's abilities by memorizing their AIM, potentially allowing her to become the eight level 5 esper in Academy City.