76%Strong matchBroken Universe - Tower Defense
90%28490% positive reviews, Very Positive across 284 reviews·Tower Defense · 2D
—Defend your base across four unique worlds in this 3D tower defense game. Battle waves of monsters, conquer 20 campaign levels, and climb the global leaderboard in the endless mode.
Galactic Siege
SteamGalactic Siege is a 3D tower defense game where your mission is to hold the line against relentless waves of enemies. Build, upgrade, and adapt your defenses across four distinct worlds, each introducing unique enemy mechanics and challenges.
Can you survive the campaign and climb the global leaderboard in Unlimited Mode?
🔹 Four unique worlds

Each world introduces new environments and enemy types that force you to rethink your strategies.
🔹 20 Campaign Stages Each world introduces its own mechanics and enemy types while building on challenges from previous stages. No two worlds play the same, and each pushes you to develop new strategies
🔹 9 Core Turrets

Experiment with a wide arsenal of defenses, from rapid-fire guns to heavy artillery and unique towers.
🔹 Over 120 Enemy Types

Face a massive roster of enemies with different abilities, behaviors, and weaknesses.
🔹 Active Skills

Take direct control of the battlefield with four devastating skills:
AOE damage to clear groups.
Freezes enemies in place.
Enemies take more damage.
Buffs all turrets in range.
Skills can be upgraded via a skill tree, using points earned by defeating waves.
🔹Research Center

Unlock permanent global upgrades that affect all turrets:
Increased damage
Faster attack speed
Extended range
Stronger slow effects
Reduced skill cooldowns
Every upgrade changes your long-term strategy and increase the price of the next upgrade.
🔹 Unlimited Mode

Survive as long as possible against endless waves. Compete on the global leaderboard and prove yourself as one of the top defenders.
🔹 4 Special Turrets

Four additional unique and special turrets to help you kill as many enemies in the unlimited mode.
🔹 Global Competition Your scores in Unlimited Mode are ranked worldwide. Will your name make it into the top 100?
Steam data © 2026 Valve Corporation. Trademarks are property of their respective owners.
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The best games like Galactic Siege are Broken Universe - Tower Defense, Defense Zone 3 Ultra HD, Siege of Centauri, 2112TD: Tower Defense Survival, and Infested Planet.
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