I would invest in a gambling website.
Investing like in real life , just depositing money there and getting a piece of the cut or just playing casino?
I hope its not the second part of the question ,otherwise you are all f up.
By 'invest' they mean to buy an ownership stake in a gambling website, and 'be the house.'
Now, I don't know whether that is more or less risky than just playing online slots. I guess it depends on whether you know what you are doing - i.e. how to manage an online gambling site, etc. If you are not bringing anything to the investment table other than capital, then I'll bet your odds are better playing slots.