Best support?

Janna,Soraka,Blitzcrank,Taric and Alistar are always good picks

as an off tank suport same story as Shen

You need alot of practice and you need to play defensive ALOT

I would say that Janna and Leona are the absolutely stronkest supports atm. Leona is relatively difficult but damn, if you master her she can easily turn a game to your favor!

I'd go with Janna or Alistar.
Reasons:

Alistar - He has great CC for late game and he's also a tank, but can heal as well. Unlike Soraka or Janna.

Janna - Her ult is amazing. Howling Gale is really annoying to their AD carry at bottom lane.

Janna, Leona is good but i'd say a bit overated

I'd say Karma is a VERY good support if you know how to play her, and alot of people don't know about her.
She hits hard; she can heal quite a lot in a teamfight if you can play her.
Shield that hurts and it is VERY strong.
Her W can also hurt enemies quite a lot speed/slow down.

IF you can play her,which most won't/can't;unfortunately. :/

AP mid Karma works too....

Sona is a good support too :)

Nunu seems to be very underrated here, only 1 person mentioned him.

My personal favorite is Janna once she has enough mana and cdr to spam everything because it's hard to do anything against being tornadoed every couple of seconds... Lulu is a good support because she's has the most versatility with the double effects of all of her abilities... Karma has 6 levels on all of her abilities which means they level up less each time but each level happens sooner and her ult, available right away, allows bonus effects and her q (I think it's q) CAN ACTUALLY DO DECENT DAMAGE omg who knew? She's kinda tricky to play with her tethered slow/speed up which takes time to get use to but once you do, no one can really escaped your team in a teamfight.

Just my two cents but I find them to be pretty good bets. Support tanks can obviously also work as they help out the team while tanking damage in the middle of a fight but I'm not a fan of getting in the middle of things when my job is to assist my team... it's just too much on my plate to deal with (I always have a tanky Darius on my team in the middle guillotining everyone anyway xD).

-Gruuk

sona.
damage source. heal. ms boost. stun. damage aura.
what else do you ask for?

I'd actually say sona is one of the worst supports at the moment