6 free tools for games, 3 of them fully open source. Every one reviewed, with its licence and the paid apps it replaces.
2D and 3D game engine with its own editor

Animated sprite editor and pixel art tool

Level editor for tile-based and free-form game maps

Data-driven game engine written in Rust
Lightweight engine for 2D and 3D cross-platform games
Real-time 3D engine for games, film and visualisation