Indie Games Week celebrates the App Store’s catalog of incredible games made by independent teams like Bippinbits, developer of Dome Keeper.

Monsters are attacking your base—and to stop them, you’ll have to dig deep. In the strategic tower-defense game Dome Keeper, excavate alien soil for vital resources, then head back to the surface to fight foes rushing your domed HQ. Here’s how to survive this action-packed gem:

Whether you’re under attack by giant-fisted Muckers or projectile-hurling Flyers, you’ve got one goal: Take them out before they shatter your dome. Thankfully, you’ve got loads of weapons to deploy, depending on your dome type—artillery domes launch mortar shells and homing rockets, while sword domes have a giant thrusting lance. Back off, baddies!

Using drills, bombs, and even a burrowing pet dinosaur, mine deep under your dome for valuable elements used to upgrade your defenses. But once you find ’em, you’ve got to haul ’em to your base—and your jetpack can carry only so much at a time. Fly them back up before an alarm signals the start of an enemy assault.

The longer you survive, the more tricked out your dome becomes. Install a revolving buzz saw or monster-repelling spray. Add a teleporter to quickly beam elements you’ve mined back to base. Unlocking game changers like these will get you closer to the powerful relic buried deep that’s key to fending off the final assault.

Early attack waves are pretty light, so before upgrading your dome, upgrade your miner. The sooner you boost their drill and jetpack, the faster they’ll be able to locate resources to upgrade everything else.