Prepare for launch, we’re off to Jupiter with Elk Studios newest celestial instalment, IO Slot.
Elk Studios have no doubt seen success from their previous, and quite similar instalment Cygnus, and are hoping to repeat its success with their newest stellar voyage.

This time, instead of gazing up at the constellations from the pyramids of Giza, we’re up there with them as we board the Casino Space Station looking for wins that are out of this world.

IO – Written in The Stars

The theme is relatively simple, but it’s certainly interesting to look at. Aboard the neon lit space casino looking outward we can see Jupiter’s moon IO, and the vastness of space. It may not be much, but it is space after all, and it looks like it’s been designed rather well.

Elk Studios have done a fantastic job with the music though, this groovy beat will really get you in the mood for a space adventure.

3 or more matching symbols on consecutive reels, starting from the left-most reel will form a win. A wide array of betting options is available for players to choose from with betting starting from 0.20 and capping at 100, and those who are familiar with Elk Studios may also be familiar with their betting strategy mechanic. It’s certainly an interesting way to bet and serves the following functions:

  • Optimizer – Bets a % of the balance
  • Leveller – Raises after 5 consecutive losses
  • Booster – Raises on loss
  • Jumper – Raises on win

The Base Game Of IO Slot

Those of you who have played and enjoyed Cygnus will find the game very familiar. Once again, wins are paid from left to right with 3 matching symbols and you’ll begin each spin with 4,096 ways to win.

4 high paying symbols and 4 low paying ones make up the composition, with your high paying symbols being a 7, Diamond, Clover and Star, and your low paying symbols represented by the classic A, K, Q, J.

A Wild symbol is also present which will substitute for any regular symbol.

Game Provider Elk Studios
Maximum Bet 100
Maximum Win 5000x
Paylines 4,096 – 262,144
Release Date 02/06/2020
RTP 96%
Mechanics Video Slot
Volatility Low
Reels 6
Minimum Bet 0.2

IO Slot Pay Table

Avalanche – Big Part of IO

All symbols part of a win will explode and disappear, and new symbols will fall in to replace them. As long as new winning combinations appear, then the avalanche will continue. You’ll also benefit from an extra row with each avalanche.

Adding an extra row really opens up the game for those huge hits, and reaching the maximum 8 rows will mean you’re playing with a huge 262,144 ways to win. If no winning combinations are made, then you’ll start the next spin with a standard 4 rows and 4,096 ways to win.

  • 4 Rows: 4,096 ways to win
  • 5 Rows: 15,625 ways to win
  • 6 Rows: 46,656 ways to win
  • 7 Rows: 117,649 ways to win
  • 8 rows: 262,144 ways to win

A gravity mechanic is also at play here, when wins or an avalanche occur symbols will naturally gravitate towards the left of the screen where there is room to do so, only falling to the right when no space is available to them on the left.

This game is just Cygnus, right? Wrong. We’re not on earth any more, and the space casino has some otherworldly tricks up its sleeve.

Charged Wild

The Charged Wild acts like a normal Wild in function with the distinctive difference that it has 4 charges. This means that instead of disappearing when used as part of a win, it will use a charge. Once these are depleted the wild will then become a regular wild and disappear when used as part of a win or next spin.

Wild Forge

A Wild Forge will fill an empty space below with a multiplier wild. The Wild Forge itself is a blocker but carries a multiplier value initially set at 2x. The multiplier value will increase for every empty space directly below itself that it fills. The Wild Forge turns itself into a multiplier wild with the multiplier value it carried with it when it occupies a space at the bottom of the reel.


You can’t have a space-themed game without lasers. Thankfully, we’ve plenty of lasers aboard the space casino. A laser will land on the reel and will point itself in a certain direction and shoot, removing itself and all symbols caught in the firing line.

However, two lasers can land at one time and if the beam from the two lasers intersect, then all symbols up to the point of intersection will be turned into wilds.

IO Slot Free Spins

3 scatter symbols in view during the base game will trigger the bonus. 7 free spins are awarded and rows for the duration of the bonus will be 8 high, meaning that you’ll have 262,144 ways to win. 3 scatters will also be needed to re-trigger additional free spins.

During the bonus game, all Charged Wilds and Wild Forge symbols will remain and drop to the bottom of the reel in between spins. The Charged Wild will use one of its charges during the transition to the next free drop.

Wild Forge symbols that reach the bottom will turn into multipliers with the multiplier value they carried. Free spins will end when no spins remain or if the maximum win has been reached.

IO Slot Free Spins

Our Verdict

IO may share some similarities with Cygnus but it’s great in its own right. The Wild Forge, Charged Wilds and Laser features really add a bit of extra excitement to an already exciting game, and each can Certainly help in getting those big wins.

We love the avalanche and gravity mechanic, and the possible ways to win are mind-blowing.

IO is a high volatility slot with a 96% RTP so those who are looking for more frequent wins may find it’s not for them, but in our opinion, you should definitely give this a go. It’s light-hearted, fun and easy to relax with, and perfect for you Sci-fi lovers.