5. Alistar
Coming in at number five is Alistar. Alistar is a tanky support that is good at initiating fights, and has great sustain in them. He is very strong in the mid game but some of his combos are hard to learn.
4. Nautilus
Nautilus is a tanky support that has very good cc and can initiate fights with the click of a button. He has great base damage and scales really well into the mid and late game.
3. Thresh
Thresh is one of the most mobile supports in the game. He is great for starting fights, and getting his team out of them. He has good cc and has decent damage for a support.
2. Soraka
Soraka has a root, silence, good zoning, and a TON of heals. Soraka can keep her laner alive for a long time in the bot lane and she is great for helping carries in team fights.
1. Janna
Coming in at number one is Janna. Janna is great for disengaging and saving people from getting picked off. Janna has very good mobility and her ultimate can really help out in team fights. Her shield will scale throughout the game, strengthening her team until the enemy team can do anything about it.