- That One Achievement: Given they're the only form of progression sans high-scoring, it's no surprise that certain challenges of Chuzzle can get... a little frustrating. As a fair note, basically any of the ones ending in an exclamation point are very difficult.
- Big Boy - Don't pop a single Fat Chuzzle during a run. Given that you can easily get, and then lose, a Fat Chuzzle completely out of your control due to drops, it may be tempting to just grind out Casual Level 1 and spend all your points on hints... Except Level 1 has no locks, either, making this extremely tedious, all while juggling your progression to as to not get too far and put your run at extreme risk. Add to that the fact that there's not a single level that has locks but no Fat Chuzzles, and you have a recipe for either the longest Marathon Level you've ever had, or a horrible Luck-Based Mission.
- Chuzzle Bingo! - Pop 6 chuzzles, straight along the board. Once again, you have to effectively set up for this, this time using luck to get a full row of six. This can be helped by Fat Chuzzles, but only somewhat—the luck factor will still be present no matter what.
- Speed Master! - Clear 2 levels in Speed Chuzzle without a single warning. Not a lock, but without even getting the warning ping. Naturally, if you do this on anything besides the first 2 levels, you're likely crazy; even besides that, it'll take a lot of quick thinking and VERY good dexterity to prevent a warning ruining your run.
- Speed Demon! - Clear 5 levels in Speed Chuzzle without a single lock. If you're not a speedrunner, get ready to learn their strategies—this requires even quicker thinking than the aforementioned Speed Master!, despite the seemingly more forgiving timing. Let's just be glad they didn't combine the two challenges...
- Flawless! - Play an entire game "without making a bad move". Effectively, you can't make an invalid move that the game undoes for you. If you're not observant and very steady with your hands, get ready to suffer. A shaky hand with a trigger finger on a row with a lock is all it takes to invalidate the run, and if you're planning on tackling any other challenges in the process of this? Yeah, have fun.
YMMV / Chuzzle