MF fits very well into lots of teams though a few well timed aoe's combined is also gg (think galio, amumu, sona, morgana etc.). plus shes an insanely good mid laner... almost too good.
Played a game a while ago (before MF took any nerfs or anything) where we had a fairly ideal lineup apart from a hero that could take on MF in mid. I ended up beating MF marginally on Shen in the end, she had to keep distance and i could farm happily with a level in feint, its not optimal for the skill order but it worked in the end.
I'd say I'm a competent MF player but there have been times where people have really got me when I'm mid lane against them. Played against an Urgot the other night and the guy really spanked me hard early game, it's just lucky during the later phases Urgot isn't anything special and I managed to take revenge. Lots
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