Developers don't advertise codes inside the game itself. Instead, you need to hunt for them:
Alien Zone Plus is a mobile arcade-style action game where you defend against waves of alien enemies, upgrade weapons, and survive as long as possible. It leans into retro sci-fi aesthetics with simple touch or tilt controls. The “Plus” version typically implies ad-free or enhanced mechanics compared to a free original. alien zone plus gift code
First impressions:
YouTube and Twitch streamers often partner with the game to offer exclusive creator codes (valid for 48 hours). Developers don't advertise codes inside the game itself