well what are you into support, adc, ap, etc.?

probably tristana longest range at lvl 16

Tristana, Tryndamere, Amumu, Teemo or Singed.

Well the most game-changing 135o champ is Amumu cuz of his ult, the most OP is def in my opinion Tryndamere or Tristana because their lategame is the one of the strongest ones in the game, they're not that good early though and very farm dependent.

Causes wrote Well the most game-changing 135o champ is Amumu cuz of his ult, the most OP is def in my opinion Tryndamere or Tristana because their lategame is the one of the strongest ones in the game, they're not that good early though and very farm dependent.

Although anyone who can't farm with Tristana's aoe damage passive are mentally handicapped

S.I.N.G.E.D just bought him on new account far out he is good.

Twisted Fate, no doubt. He can dominated if you get his attack speed and ap up and a little

Cho'Gath is pretty good
just bought him and i like it so far
if you do buy it you should buy ability power stuff

Teemo, he's super strong if built right and can be the most annoying champion to fight against. He is on the rotation this week which should give you some time to try him out and see if you like his play style. Best build would have to be Liandry's Torment -> Berserkers Greaves -> Runaan's Hurricane -> Frozen Mallet -> Wit's End -> Banshee's Veil
This build gives a low amount of ability power, but the attack speed and survivability late game is awesome. The liandry's torment with the poison passive is ridiculous early game because it allows you to hit the enemy a few times and still do a lot of damage. Teemo can be crazy good even when not in the battle if you know where to place your mushroom traps. Overall, he's beast.

Anonther good one would be Twisted Fate, just build Attack Damage and Attack Speed and he gets to be ridiculously over powered and you can just auto attack to do good damage combined with his W ability.