Operation: Outbreak Idle

Command automated military defenses, upgrade your fortress, and survive massive zombie waves in this action-packed idle defense game. Build powerful defenses, unlock upgrades, and hold the line against endless undead hordes.

At a glance

• Platform: Windows.
• Genres: Casual.
• Release date: Sep 4, 2026.
• Steam user reviews: No user reviews.
• Delivered as a Steam library entitlement — activation is handled by Steam.

Minimum

Recommended

System requirements as published by the developer on Steam.

Activate on Steam

• Open the offer above — it takes you to this game's official Steam store page.
• Buy it there, or if you bought a key elsewhere, open Steam and choose Games → Activate a Product on Steam.
• Enter the product code exactly as it was issued to you.
• The game appears in your Steam library — download and play.

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