what happened if i win a game that is a russia key?i am european

If you activate a Russian key you'll become Russian and you will be sent to GULAG.

I agree with Mariganza since theres no country filtering whats the consequences if i win a country restricted key without know and activate it ? i heard steam block the account

In Soviet Russia, Key wins You.

You're fine unless you use IP changes to fake you're from Russia. Region restricted keys are not allowed anyway, so don't worry.

ha :/

It'll just say that you can't activate that key because it's region restricted, and then you go back to Steamgifts and mark the gift as "not received" and report the user because region restricted keys are against the rules here.

some people said it may ban steam account or not. there is no official Valve's answer as I know.
but I can say to you what proof of purchase is very difficult when the key which you activated has been revoked or got similar problem.

fyi, russian key has 3 different type.
first, no restriction.
second, activation is works in everywhere but can play in Russia or CIS only. you need VPN for play it if you don't live in Russia.
third, activation and play in Russia only.

Trade with some russian smartass, maybe you can get something good from it :D

well...small part of Russia is in Europe :| and I DONT CARE about if its russian,sea or amercan key I will just headbutt it and it will become international!