Io is a space-themed slot from ELK Studios with a reported RTP of 96.0% and medium-high volatility. The game uses gravity mechanics, so symbols slide left and right as they fall, with rows added after wins up to eight rows and 262,144 ways to win. This structure is designed around cascade-style play rather than fixed paylines.
The paytable includes standard card symbols alongside themed icons such as diamonds, stars, clovers and sevens. Special features include a Laser symbol that clears symbols in its beam direction, Wild Forge, which creates multiplier wilds in empty spaces below, and Charged Wilds that carry four extra lives when they take part in wins.
A demo version is available near the launcher, allowing players to play for free and practice before playing for real money. The free drops bonus game awards seven free drops, runs with eight rows, and can be retriggered, with Charged Wilds and Wild Forge symbols collected between drops.