Deductum 1.0 was actually released a couple days ago but today I also added a free browser-playable demo. The music may not loop correctly in the demo (because of a bug in Godot's web export) but works in the full version.The demo includes conjunction and implication (AND and IF...THEN). Disjunction and negation (OR and NOT), which allow more interesting levels, are included in the full version. Sandbox is also a non-demo feature.