Reksai is a poor excuse of a champion. IMHO
Reksai has a cool concept, the thought of being a bruiser "hunter" is nice but what she lacks in being a hunter she makes up in damage, yeah she has great damage but who cant do her job better? Udyr does it better and with only a 6 second stun cool down and with a massive mobility burst. nocturne and reksai pretty much have the same ult except noct actually does damage, I feel limited when i play reksai and im so easily kited, im mostly jsut there to burst and then get out while my team cleans up for me. I honestly think she would be a stealth champion. She doesn't feel very hunter like at all. A hunter has the element of surprise like khaz and rengar. Everybody knows where she is because of a sight ward...rengar has a stealth i dont see why her burrow shouldn't have a "stealth" like ability. Im sorry but i simply just dont like her. Shes kinda garbage. Maybe i just suck with her but she just doesn't feel like a hunter at all. Shes too easily kited. She doesn't even have a slow. Like all the hunters do.
or 
in the jungle. You shouldn't try to teamfight or skirmish unless you know you have the man advantage. It's pretty easy to pull this off as Rek'Sai because you have INSANE mobility with your tunnels if you put them in the right locations. You couple that with her fast clears, and she can put pressure all over the map. Once you realize that her game is more about out-running your opponent then out-fighting them, then her ult starts to seem a lot more useful.