Pet Simulator 99 Worlds Guide
Each world is a chain of areas with better eggs at the end. Push to the last area before dumping coins into that world’s eggs. New worlds raise breakable HP — if you stall, hatch the previous world’s best egg, then continue.
Spawn world
Early areas teach the loop. Rebirth shrines appear at set areas (community guides still cite 25 / 50 / 75 / 99 as major gates). Treat the live shrine as the unlock, not a YouTube screenshot.
Later worlds
Pixel, Tech, Space, Fantasy, and whatever the current last world is all follow the same rule: last-area egg first. Fantasy-style worlds often want a fat coin bank because their shops are a separate economy.