Games like Alien Robot Monsters

"Ancient Planet" is a Tower Defense game where you defend an ancient civilization's stronghold from invasive alien hordes using upgradable towers and diverse strategies. The game features 40 unique levels, a variety of enemy types, and improvements that can be reset and redistributed at will. The game's storyline and setting are based on the memories of intergalactic war veterans and were created with input from the High Council of Intelligent Civilizations of the Galaxy.

"Revenge of the Titans" is a real-time strategy and tower defense game where you must defend Earth's bases from relentless Titan attacks across the solar system. Assemble defensive positions with turrets, droids, barricades, and mines, while managing funds by mining nearby resources. The game features a 50-level campaign, endless and survival modes, and numerous buildings and technologies to research.

"2112TD: Tower Defense Survival" is a futuristic tower defense game with strategic base building elements. Defend your refinery from alien invaders across procedurally generated levels with a variety of turrets and special abilities. Upgrade and customize your arsenal to survive increasingly challenging waves in this intense, sci-fi tower defense experience.

Iron Marines is a real-time strategy game that puts you in command of a powerful army of space-age soldiers. Battle against alien threats and challenge challenging missions using cutting-edge technology and cunning strategies. With a variety of units, upgrades, and heroes to choose from, every playthrough offers a unique and engaging experience.

"Kingdom Rush Frontiers" is a challenging tower defense game with numerous upgrades and special abilities. Players defend their kingdom against various enemies, such as bandits, dragons, and mummies, across diverse stages like deserts, jungles, and underwater worlds. The game features heroes with unique abilities to aid in battles and adds a reinforcement system to strengthen towers during intense fights.

"Super Sanctum TD is a retro-styled Tower Defense game that focuses on strategy, customization, and replayability. Carefully plan your maze and build advanced structures to defend against alien hordes, using active abilities to tilt the battlefield in your favor. Level up and gain access to Perks, allowing you to specialize your strategies and master the game on all difficulties."

Defense Grid: The Awakening is a tower defense game where players protect their base by building fortification towers against incoming enemies. With 8 hours of main storyline and many more in challenge modes, each level is highly replayable and can be solved in various ways. The game features 15 different enemy types that increase in strength over time, providing a wide variety of challenges.

"Kingdom Rush" is a defense strategy game where players protect their kingdom from invading forces across various landscapes. Players can utilize a variety of tower upgrades and abilities, as well as command troops and summon reinforcements, to fend off 61+ types of enemies. The game boasts hand-drawn cartoon art and promises hours of addictive gameplay.

"MarZ: Tactical Base Defense" is a strategy game that challenges you to build a defense base and fight off zombie hordes on Mars. The game features a 20-mission story campaign, skirmish mode with customizable waves of enemies, and an intense "Outbreak" mode. Utilize powerful terraforming tools to create custom maps and share them via Steam Workshop, and research new upgrades for your towers. Recently updated with increased technology options and reworked balancing.

Warstone TD is a fantasy tower defense game where players strategically place towers and units to defend against hordes of enemies. With various game modes, heroes, and towers to choose from, each level presents a unique challenge. The game features a compelling story campaign, online PvP, and co-op gameplay, offering a rich and immersive tower defense experience.