First I ever played: Sivir
First I ever mastered: Pantheon

My friend recommended Ashe to me, so that's who I played first. Incidentially, I also bought her first, since she's cheap.

Shaco. It was a solo game, no bots, no other players. I declared war on the jungle creeps with my Jack-in-the-Boxes.

Nunu, with my first 450 IP. I did so poorly that I nearly quit LoL completely. Luckily, Tristana was free! I did much better as Tristana.

I didn't play the weekly rotation champs for months, for some reason.

Fiddlesticks on a 10fps computer, lol i dont even remember how did i win that

Sivir!

Morgana

Rammus. Ok

TF.

I dominated due to prior experience with Action-RPGs.

It is a bit vague on what my "first" was. My true "First" was Ashe, who to I played with great success until I bought Katarina. After playing Kat (and failing horribly), I eventually bought Nidalee, who was my #1 main for at least 400 games. I still consider Nidalee to be my go-to champion if I want to win nowadays, but I play her a lot less.

So yeah, that's my story.