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Begin with lessons or foundational guides, then move to debugging, safety, and advanced operations. Each article states the evidence level it actually reached.
Open the first guide →SYSTEM 05 · 5 GUIDES
Controllers and Expansion
Upgrading, downgrade recovery, reserving, claiming, safe mode, and remote control. This page connects the system overview to focused lessons, diagnostics, and operational boundaries.
RELATED TOPICS
Browse focused archives
Controllers, Creeps, Energy, Defense, Debugging, Rooms
SYSTEM MAP
Controller control and upgrade chain
Controller safety depends on Energy supply, the Upgrader, range, upgradeController() results, and progress across multiple ticks.
- 01Energy supply
Container / Link / Hauler
- 02Upgrader
Carries WORK and Energy
- 03upgradeController()
Check range and result
- 04RCL / downgrade
Watch progress and downgrade pressure
- 05Structures / expansion
Unlock capacity or move into reserve/claim
05
Published guides in this system
Use the labels to distinguish sequential lessons, task-focused guides, debugging workflows, safety pages, and references.
- LessonScreeps upgradeController(): Build Your First Upgrader Loop10 min read · Beginner
- GuideScreeps activateSafeMode(): Prevent Same-Tick Intent Overwrite17 min read · Advanced
- GuideScreeps Controller Downgrade Recovery: Verify Emergency Upgrades15 min read · Intermediate
- GuideScreeps reserveController() vs claimController(): Verify the Exact Mission22 min read · Intermediate
- GuideWhy a Fixed Screeps Upgrader Is Not Upgrading20 min read · Intermediate
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