tld screams spam in my opinion. I think i would make it much more difficult to see any decent traction in the serps. Look for more reputable tlds. .com .co.uk .info etc.
A domain like “free online slots” regardless of the subdomain would be a risky buy. The user intent when arriving on a website like this is to play for free. You’d have to get LOTS of traffic before really making any real money…