All JulFlux games and DLCs are 25% off on Steam from May 15 to 22:
https://store.steampowered.com/app/1757130/Pong_Temple/
https://store.steampowered.com/app/1493660/Spiky/
https://store.steampowered.com/app/1440700/ChessExtra__Dev_Support__Pieces_Full_Design/
https://store.steampowered.com/app/1444810/ChessExtra__Dev_Support__Castle_Customization/