You don't even need an ss to prove that it happened, the game already has it saved under their statistic information. All you have to do is go to the player info and highlight all the champs then go down the scroll bar and click pentakills; their charts will show if a champ has a penta or not.

Off Topic*

I really like their new interface after log in screen.

[quote=Symphs]My latest penta was with Anivia.

...

I had 4 afks in my team ( premade normal game, and when their internet went down, they all went down ) so the enemy team gave me a penta :I, does that count?[/quote]
If it's with my favorite champ, then yes

My latest penta was with Anivia.

...

I had 4 afks in my team ( premade normal game, and when their internet went down, they all went down ) so the enemy team gave me a penta :I, does that count?

got 2 pentas in one game. WITH FIZZ.
half the time we screwing around though, though that was a year ago.

Grats, nothing beats that first initial rush you get when you realize that you can potentially get that Penta, my first one was on Yi, those Yisets baby, second one was on Ziggs alittle more heartpounding almost missed that last q.

I've had around 25 But gratz on your first one, I understand the joy of it haha.
First was Master Yi, and I believe that last one I had was Lissandra. Crazy hard with mages.

[url=http://i.imgur.com/qH1fJAn.png]Not hard to penta against a Singed jungle, but grats anyway. I've never penta'ed in ranked because I don't usually play carry roles.[/url]

[quote=tsubasa128]ingame name: futontsubasa

http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/1511320181/202397104[/quote]

btw hyperlink doesnt work for these kind of stuff

[quote=Wordolio]video or it didnt happen.[/quote]

ingame name: futontsubasa

http://matchhistory.na.leagueoflegends.com/en/#match-details/NA1/1511320181/202397104

Edit: aw looks like it only shows the game from a while before

video or it didnt happen.