I can't recommend this one, sadly. It's a fun base concept, but it swings from way too easy to frustrating in an unfun way without ever actually touching the middle ground in between. The initial 'alphabet' puzzles always begin with the same letter, and are accompanied by a clue, which combine to make them almost trivial, but once you get past that there are neither initial starting letters nor clues, giving you no idea what words the game actually wants beyond a certain number of letters.

What follows after that isn't exactly 'challenging', but instead just aggravating, finding words in the grid only to be rejected by the game, guessing randomly at which of them might be correct. It essentially turns it into a small word-search without any actual word list to build off of, which just isn't fun, in my opinion