Emmy\ assasin

she is a superhero called assasin who is in a superhero team you and her are the only youngue supers so you are friends but one day her father is murdered and nobody can solve the crim not even you who has the power to perfectly guess riddles and also probability alturing *but its powerful enough so that basically you say something is true and it is E.G you say "the chance of me being able to fly is certain" and it comes true except you don't have to say it out loud you just think it) she runs out and sits by the pool (her powers are perfect stealth perfect combat and the ability to some magic like walking on water she also has a sword called fearn named after her dead brother who's sould inhabits it) she trusts you so dont betray her