Hundreds of enemies on-screen - Defend against an ever-increasing swarm of hostile alien creatures. Hundreds upon hundreds of visible enemies marching upon your base simultaneously.
Build and upgrade towers - Choose from an assortment of towers to build that fulfill the needs of various situations. Upgrade those towers in different and unique ways.
Learn and use abilities - Acquire varied types of abilities to create unique combinations and use at crucial times to turn the tide of the battlefield.
Randomized upgrades - Choose between three sets of upgrades every upgrade phase. Every set of upgrades consists of positive benefits for you as well as upgrades for the alien swarm. Use tactical decision-making to create wild combinations while adapting to evolving strengths of the alien menace.
Campaign mode - On the run in a hostile galaxy and low on resources, play through a non-invasive story on customized scenarios for each map.
Skirmish mode - Customize any map to match your own desired specifications. From which enemies are present to speed of upgrades, difficulty can be fine tuned to how you want it.