Archaeologist Achievement in The Mooseman
Collect all artefacts
How to unlock Archaeologist
There are a total of 52 artifacts to collect in the game, and which ones you have can be checked by pressing at any time. Some of the collectibles are story related, many are hidden just off the main path, and a bunch are obtained by inputting specific button sequences in specific areas. It's these latter ones that will be extremely difficult to find without a guide.
The video walkthrough in the "Sunset" achievement solution includes all collectibles. I highly recommend following it because you will assuredly miss some without it. If you do miss any, you can use chapter select after you complete the game to go back and get whatever you missed.