Actually I'm looking for gambling sites with minimum loss. Here is few sites I've tried till today.
Bustabit - Total loss of $60
Primedice - Lost $10
Sathoshimines - Profit $4 (This site is getting harder day by day)
unknown - profit $15 (Invested very little site pays in mbtc site like this I'm looking for)
If you have any real poker game then recommend me I'll try it. Similar sites like taxas holdem poker.
I'm not aware of any site that has a 'minimum loss', it's all just based on luck and variance.
So you're definitely talking about gambling, right? When you say invest, you mean invest to gamble? Still not really clear....