: Stealth missions are a primary source of free gems. A common "glitch" or trick involves mastering the radar; when the alarm triggers, flying in a large, medium-speed circle can often keep you alive through the bullet storm.
: Investing gems in a five-star copilot is mathematically superior to many other upgrades. A high-level copilot can increase your power by nearly triple on Tier 2 planes, making difficult levels significantly more manageable. Progression Warning 1945 - Airplane shooting games Hack
: To dominate weekly events and secure the 400-gem gold medals, some players intentionally keep their single-player campaign rank low. This prevents them from being placed in higher-tier competitive brackets before their planes are powerful enough to compete. : Stealth missions are a primary source of free gems