One of the best games on iOS has a big new update out today which takes hearty tower defenders out onto the frozen tundra.

The new Winter Storm expansion adds two new levels, three new enemy types, and two new Viking heroes to join your army. Plus, the already challenging game is layering on a new hard mode for players who just can’t get enough punishment. 

The new update is all about Warlord Ulguk-Kai and his army of trolls as they invade through the two snowy new stages. Helping you out along the way are Winter Storm’s two new heroes; Ingvar is a Viking werebear, and Elora soothes the savage trolls with bardic music. 

For those not in the know, Kingdom Rush is a standout tower defense game available on multiple platforms, but today’s update only applies to the iOS and Flash versions for now. Players set up an array of archer, artillery, and other towers along the game’s prescribed paths to block charging demons, spiders, and other baddies. The game is known for its intricate balance and lengthy campaign. 

If you haven’t played it yet, you’re missing out on one of the best tower defense games out there. If you have played it, you’re probably already logging into your iTunes account to get these new levels.