Is Ponzi sheme legal if it’s clairly explained

Hello all

I found this ( ) on the dapps subredit. And i have so interogation after reading their website.

We all know bitconnect, it was a ponzi sheme and some people was held in custody after that to find the person who created bitconnect and advertise about that. Some other poeple like Madof who created ponzi sheme went to jail after that. But all of them lied about the true working of their sheme.

So about Unkoin, all is clear no ? They exlpain all about their sheme, how it work, how to recover your eth if the website is down and the smartcontract is opensource. it seems fair no ? It's like an etheroll, loto games or something like that no? So is it legal ?

Thanks for your answers