Hellgate or weekly ranking?

I've only been playing this game for 3 weeks so I don't really know much about it. Recently I've tried to clear a hellgate and managed to reach the 20 lvl boss. After spending a lot of wines I won and received a hell envelope but it only gave me a barbaric warrior (which is lame since that's one of the cards I got from evolving normal cards). And one of my friends that literally hit the boss once got the week's card(I had already inflicted more than 1million damage so there were only 3 participants)! I was so dissapointed! I really thought that after defeating the hellgate you can only get the week's card! So how does it work? Is there a specific percentage that you can get that card? I should really know if it worths spending wines on hellgates at all? Or should I save them and try getting to the top 500 weekly ranking? (On the ranking is it 100% certain that I will acquire the weekly card or can it give me a different card again?)

I have heard that it's a 50% chance when opening the envelope to get the weekly monster. Should be 100% if you ask me..

Haha... I agree. I've found out the ratio of the weekly card as well. It is 50%. and 10% for any other sr card. Also I guess HG are much better than the weekly ranking. We can get more envelopes each week and it has better reward cards usually.