The two most obvious feature symbols are the wild and the scatter symbol. The wild works in the usual way, switching in for any symbols you are needing to complete a winning payline. It also gives you a 2x multiplier on any wild combination wins, so can be doubly helpful in delivering a better return on winning spins.
The wild symbol won’t substitute in for Thor’s Hammer, the scatter symbol. They also lose their wild function during the Wild Storm feature, a randomly triggered bonus that turns multiple reels into wilds. This also prevents any retriggers, but I’ve found it to be a pretty profitable bonus whenever it comes along – with so many wilds in play, it feels harder not to win big when the Wild Storm hits.
Finding three or more of the Thor’s Hammer scatter symbols anywhere across the reels triggers the Great Hall of Spins feature, the key element to winning big in Thunderstruck II. As you trigger the bonus on successive occasions, the game opens up, with more free spins and additional multipliers being introduced.
The Great Hall of Spins
There are four stages of the Great Hall of Spins bonus, where you can pick up an increasing number of free spins – plus a corresponding multiplier for your troubles.
Valkyrie Bonus: This is level 1, your first and fourth bonus feature. It’s worth 10 free spins, which are retriggerable, plus there’s a 5x multiplier for anything you win. I’ve found myself retriggering free spins a couple of times in this first bonus round. And you certainly won’t be complaining if you’re landing 5x on your free spin winnings – a very juicy multiplier to keep the winnings flowing.
Loki Bonus: On your second Great Hall of Spins bonus, you’ll trigger the Loki Bonus – it’s also an option between your fifth and ninth triggers of the bonus round. There’s no multiplier, and you always have the option of choosing the Valkyrie bonus when Loki presents if you think that’s better for you. I’ve tried both ways and had good experiences with both, but it’s worth trying both for yourself.
In place of the multiplier, this bonus comes with the Wild Magic feature, which means you pick up extra wilds randomly through the bonus rounds. If you land two or more scatter symbols during the feature, you can also receive anywhere from 1 to 4 additional spins for your troubles, in complement to the 15 free spins you get to play with in the Loki bonus.
Odin Bonus: Next is the Odin Bonus, also selectable between your tenth and fourteenth times triggering the bonus. The prize is a flat 20 free spins, along with the Wild Raven feature, which allocates multipliers at random of either 2x or 3x. Landing both multipliers at once gives you the effect of up to 6x – the biggest multiplier I’ve experienced in Thunderstruck II. Again, you don’t have to play the Odin bonus if you would prefer the Valkyrie, and you’re given the option to choose which bonus you want to play.
Thor’s Bonus: The most rewarding bonus in my experience is Thor’s Bonus, triggerable by the fifteenth bonus feature entry. This means you instantly pick up 25 free spins. There’s also the Rolling Reels feature, which can pay out multiple successive wins, on a multiplier of up to 5x. I’ve always found the best wins to come from the Thor bonus, not least because there are so many free spins. But if you prefer to keep things simple, you can again revert to the Valkyrie bonus for 10 free spins and the fixed 5x multiplier if you want.