What are some free elo champions for silver?

Mid:

Ahri

• She is kind of a jack-of-all trades with her sustain, poke, and pick potential.
• Her Q and ultimate give her a lot of safety through mobility.
• Great at roaming and ganking

Xerath

• Strong burst
• fantastic poke and pick potential
• Even against hard matchups you can stay a safe distance away and still farm with abilities (to an extent).
• His ultimate is also helpful because you can pick up kills on enemies that would have escaped fights alive

Anivia

• Guardian angel passive helps survive mistakes if it triggers under your tower or near allies
• Powerful CC
• Wall is good for disrupting teamfights
• fairly tanky build path for a mage (lots of HP and shielding)

Top: I dunno, don't play enough of toplane. Quinn vs melees works well if you make good use of her passive marks and use her e to disengage. Fiora is strong. Yorick too.

Jungle:

Vi

• Strong ganks
• pretty good clear
• good dueler
• flexible (can go tank or diver or even straight damage sometimes)

Nunu

• powerful objective control
• good impact in teamfights with his supportive abilities and his ultimate.
• blood boil is really powerful for marksmen, you can use this to really amp up their power in fights

Zac

• Great sustain
• Very powerful ganks
• strong disruption in teamfights

Warwick

• Good early ganks
• Good sustain
• Great mobility from blood scent
• Flexible build, can go tank or tanky-dps