Castle Siege Defense — Free Online Tower Defense Game

Castle Siege Defense is a free browser-based tower defense game where you build medieval towers to protect your castle from endless waves of goblins, orcs, trolls, demons and terrifying bosses. No download, no registration — just click Play and start defending.

How to Play

Choose a level, then build towers on the marked spots beside the monster path using your starting gold. Press Start Wave to begin — your towers will automatically fire at any enemy that enters their range. Defeated enemies drop gold, which you can spend on more towers or upgrades. Survive every wave, defeat the boss, and protect your castle to complete the level.

Tower Types

Archer Towers fire quickly at single targets for a low cost. Cannon Towers deal explosive splash damage to groups of enemies. Magic Towers pierce enemy armor with powerful bolts. Ice Towers slow enemies down, Fire Towers burn them over time, and Lightning Towers chain damage between multiple nearby enemies. Combining tower types is the key to surviving later levels.

Features

Eight uniquely themed maps from the Green Valley to the Demon Realm, seven distinct enemy types plus five epic bosses, a deep eight-level tower upgrade system, four targeting modes, a castle that visibly evolves as you progress, and a secure global leaderboard so you can compete for the top score.

Frequently Asked Questions

Is Castle Siege Defense free to play? Yes — completely free in your browser, no download or account required.

Does it work on mobile? Yes, in landscape orientation. Rotate your phone for the best experience.

How is the leaderboard kept fair? Every score is validated on the server using a secure session system — the game never trusts numbers sent directly from the browser.