Was planing to invest on a gambling site since they said its a gauranteed profit since the house can't lose but I'm still skeptical about it, i don't have much BTC so I have to make sure whether its going to be profitable for me. What possibilities could happen to the gambling site i wanted to invest into and how am i going to lose my investment in such a manner?
Two big issues:
-site being hacked
-site owner leaving with the coins
Appart from those two possibilities, you should be perfectly fine

The third possibility is if any one win big amount then our investment profits will get hurt and it is possible because we have seen some people won big amount from these casino houses. So if you want to be safer side in casino investments then better diversify your investments. Invest on few good casinos instead of only one or two.