'Anchor' characters are basically 'Support' in this game.
The biggest 'Anchor' currently is Sona, with her Auras and support just being around her 'anchors' your team. However alot of support are capable of it
Good 'Anchor' Support:
Sona, See above
Janna, Shields, slows, knockups, knockbacks and heals all with a passive teamwide movespeed boost
Morgana, Good DPS, A CC blocking shield, a great root, and a team fight changing ult that will slow then stun
Aura Sivir, Decent DPS on her own, great at farming, as long as the team is being a team she is useful. On the hunt has been HUGELY buffed.
Lux, Double roots, AoE shields, a placeable slow that controlls the battlefield and a pewpew ult on a low CD
However if your talking about leading a team to victory by being a team leader, then tank. If your a good tank EVERYONE will listen. Ive had whole teams follow me around in a soloque because i was initiating all kinds of hell.
Alistair, 'Tankiest' tank, if your good hes amazing even in high elo. AoE stun, Knockback makes him the king of displacing people in team fights. He has a small heal for laning [and sometimes saving someones ass] and his R allows you to build DPS items and still remain an amazing tank.
Amumu, Team fight tank, bad lane phase. Has a skillshot stun, a small %health based damage aura, a nuke that hits enemies close to him, and his ult- possibley the most gamechanging teamfight ult. A 2.5 second AoE bind
Rammus, Scales amazing off armor, Powerball allows you to easily initiate and catch runners, Defensive ball curl makes you THE anti-DPS and gives you alot of survivability- Taunt is one of the best CC in the game and goes amazingly with DBC and his ult does decent AoE damage and is great for farming large creepwaves
Shen, More of a 'small fight' tank, he uses no mana, his Vorpal Blade causes you to regain a small amount of HP over time every time you hit, Feint blocks a small amount of damage, His taunt is AoE unlike Rammus, so if your good you can catch whole teams, and his ult changes the midgame by allowing him to save allies from accross the map- careful as his ult dosent scale well into the lategame