Helloween is a 5-Reel video slot machine with 10 fixed paylines, paying left to right.
Landing a Scatter on reels 1, 3, and 5 trigger the Keeper of the Seven Keys feature wheel, where it is possible to trigger one of seven features. Each of the features award 5 Free Spins, except Helloween Free Spins which awards 7 Free Spins. Scatters also act as Wilds. Scatters are not available during the I'm Alive, Future World, Eagle Fly Free, Dr Stein, March of Time and I Want Out features.
In I’m Alive, Wilds that land are held in place and expand up or down one place on each spin, after a reel is filled, they will disappear on the following spin. In Future World, any Wilds landing expand to fill the reel. In Eagle Fly Free, one Wild is flown onto the reels on each Free Spin, remaining on the reels and changing position on every spin. In Dr Stein, all instances of a randomly selected royal symbol on the reels turn Wild on each spin. In March of Time, Wilds are held on the reels and move one space to the left on every spin, once they have reached reel 1 they will disappear on the next spin. In I Want Out, Wilds that land on the reels expand in size to 2x2 symbols. Helloween Free Spins awards 7 Free Spins, with the chance to re-trigger the Keeper of the Seven Keys feature wheel.
In Helloween Free Spins the Scatters are collected over spins. The Keeper of the Seven Keys feature wheel is triggered by collecting 3 Scatters. The feature wheel works in the same way as in the base game with the same features. Re-triggering Helloween Free Spins will add a further 7 Free Spins to the total. When the Scatter collection meter is filled, the meter resets and any further Scatters on the reels are added after the feature is triggered. Remaining Free Spins continue after feature wheel is triggered and feature plays out.
After all features there is a random chance to trigger the Helloween Multiplier - a total win Multiplier of x2, x3, x5 or x10 - once spins have completed. In Helloween Free Spins the Multiplier can only be triggered at the very end of the feature and not within any features triggered within Helloween Free Spins.