Io Review

Look and Feel

Io is a futuristic-looking online slot from ELK Studios with six reels, four rows and an out-of-the-world max 262,144 ways to win. The slot starts off with four rows but extra rows may be added as play goes on. You start off this game with 4,096 ways to win, but once you have maxed the slot out at eight rows that number climbs to 262,144 as already mentioned. This ‘slot’ may look unusual in that the symbols are circular, the rows are not in a straight line and all symbols fall from above as opposed to spinning around the reels, but to all intents and purposes this is indeed a slot. The set-up is just ELK Studios’ way of being innovative, and it’s one that succeeds.


This game is not in possession of any kind of stellar progressive jackpot. The maximum you can win while playing Io is 500,000 coins. Note that the casino where you are playing this slot may enforce its own rules about the maximum amount you can win.

Play for Real Money

There are zero casinos in the UK that will permit you to play this slot for play money, due to UKGC regulations. There are many casinos in the UK that carry ELK Studios slots for real money though, including Betsafe Casino. This casino is better known as a sports book, but it still has plenty of great casino games and slots, and attractive players offers too!


You can choose from twelve bet levels when you play Io, and each spin of the ‘reels’ costs 100 coins. The minimum bet level is £0.20, and the maximum is £100.00.

Wins are paid as coins in line with the table below. You only need to land the same symbol on any row on the reels in sequence from left-to-right from the first reel onwards in order to secure a payout.

Symbol3 on a payline4 on a payline5 on a payline6 on a payline

The slot has the ‘avalanche’ feature. When you win all winning symbols drop from the reels and new ones cascade in to replace them. An extra row is added, up to the maximum of eight. Once no more avalanche wins are achieved, the number of rows is reset back to four.

You need to keep an eye (or Io) out for the bonus symbol when you play this game. If you land three bonus scatter symbols then you trigger free drops. The number of rows available is upped to eight, and the number of paylines maxes out at 262,144. During your bonus drops ‘Charged Wilds’ and ‘Wild Forge’ symbols (see later) are collected at the bottom of the reels between the drops.

A Charged Wild is one with four ‘lives’. Every time that it figures in a win it loses a life. Once it has used up all its lives it will disappear. It substitutes for all other symbols aside from the bonus symbol. There is a wild symbol too that does the same except that it only has one life.

A Wild Forged symbol fills empty space as it drops with multiplier wilds. Every time this happens the value of any multiplier created increases. Wild Forged symbols become multiplier wilds once they hit the bottom of the playing arena.

Winning combos create a laser when they vanish. When the beams from two lasers intersect, all regular symbols in the path of the laser become wilds. Once wins are evaluated, all laser-induced wilds vanish from the playing arena.

This game has a number of ‘betting systems’ that you can use if you so wish. These may increase your stake when you lose, or decrease your stake when you win. At JustSlots, however, we recommend that you do no use these betting strategies unless you are one hundred percent sure as to what you are doing.

Graphics and Sounds

Graphically, we do not think this game could be better. We really like the way that the symbols ‘roll down’ when there exists space beneath them. The symbols are colourful, but they are a little too small for our liking as it’s difficult to know just what’s going on, and what your chances are of triggering avalanche wins. What we especially like though is the slowly rotating view of Jupiter at the back of this slot (Io is the name of the third biggest moon of Jupiter).

The game is played along with a non-intrusive dance tune that’s hardly memorable, but then it doesn’t need to be. The rest of the sounds – stabs, trills and explosions – fit in perfectly with the overall experience of this slot.


This multi-featured slot is a great one to play. All these features have been seen before in other slots, but they are presented here in the perfect package. Why not fuel up your slotting spaceship, set your course for Io and play this game at one of JustSlots’ many recommended online slots or casino sites?

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