Chants of Sennaar is a great game that combines linguistic & numeric logic puzzles & stealth-lite elements in a chromatic-minimalist art style with excellent mood music. The languages themselves serve as the puzzle pieces & there's a lot of satisfaction in combing out the clues of the citadel for pieces of vocabulary to assemble an understanding of the language, then weaving the pieces between languages together to progress further through the world. It felt like a good way to stretch the brain over a weekend.

You can also pet the cat.