Overview:
- Estimated achievement difficulty: 1/10 [Achievement Difficulty Rating]
- Offline: 17 [1000]
- Online: 0
- Approximate amount of time to 1000: 1-2 hours [Estimated Time to 100%]
- Minimum number of playthroughs needed: <1 [technically don't need to finish the game for any achievements]
- Missable achievements: 8 [all non story achievements are missable; see roadmap] 
- Does difficulty affect achievements: No - can play on Casual
- Unobtainable/glitched achievements: None
 
Introduction:
Welcome to 9 Clues: The Secret of Serpent Creek, the latest Artifex Mundi game. If you're unfamiliar with their games, they're old school point and click adventure games with a heavy emphasis on puzzles and hidden object scenes. Unlike all of their games before this one, this game doesn't have any skill related achievements for hidden object puzzles or minigames aside from one for the lockpick puzzles, but those are easily covered with a walkthrough solution. There are also barely any collectibles in this one. Combined, that makes this the easiest and fastest one of their games to date. Let's get started. 

Abbreviated Walkthrough:
As with all Artifex Mundi games, there are collectibles. While there are multiple areas you can't return to, thankfully there aren't any collectibles in them. Even so, it's very easy to miss these collectibles since there are only nine, and therefore you won't know which scenes to even look for one in. As a result, I highly recommend keeping a collectible guide open while you play through the game (a great one can be found in Clue Collector (60G)). I highly recommend grabbing each collectible as soon as you reach that scene.

Aside from the missable collectible achievements, there are a number of miscellaneous achievements that are also missable, so you should be aware of them and, ideally, take care of them as soon as possible so you don't have to worry about them for the remainder of your playthrough. One is game-spanning:
 

• Complete all puzzles (i.e. minigames) without skipping them (Puzzle Master (80G))

The rest are one-off achievements:
 

• Complete three Hidden Object Puzzles (HOPs) without using a hint (Unaided (50G))
• Complete the three Lockpick puzzles in under 3 minutes total (Arsene Lupin (70G))
• Find 3 newspapers (Avid Reader (60G))
• Play with Breebo the cat (Cat Lady (60G)); refer to this one first, as it's easy to miss and is gotten very early in the game

The one game-spanning achievement just requires you to not press  during minigames. Refer to it if you need any tips. One important thing to note here is that there is no achievement for completing all HOPs without using a hint, only three of them. Therefore, as soon as you unlock Unaided (50G), you can feel free to use hints during HOPs as much as you want. As for the one-off ones, you should be able to knock out most of those within the first 15 or so minutes of the game, allowing you to play through the rest of the game without worrying about missing any achievements (aside from collectibles). The riskiest one is Arsene Lupin (70G), since the game autosaves as soon as you complete each puzzle, and if you took too long you won't know until you're done (the achievement tracking won't increase) but it'll be too late. It's therefore in your best interest to make use of the walkthrough in Last Stand (60G) to ensure you have the solutions to those puzzles handy for when you start each one.

Aside from the collectible achievements and bunch of miscellaneous achievements above, all other achievements are story related. By the time you complete the main game, you should have all achievements. The bonus chapter is not required for any achievements.

Conclusion:
9 Clues doesn't add anything unique or interesting as far as gameplay, although it does have a more open feel since the entire game takes place across all of the same accessible areas. Both the minigames and HOPs felt extremely easy in this one, with almost no challenge whatsoever..On top of that, thanks to some easier miscellaneous achievements, this is one of the easier and quicker Artifex Mundi games. Congrats on another quick (and hopefully enjoyable) completion!