I LOVE this game! I own about 30 or so boardgames, but most of them see the light of day about 3-5 times a year. So far I've played AH3E about 35 times, under 6 months!

The only pain point in the game's setup is making the monster deck..

How can I purchase additional monster decks so that I will have one per scenario? (Buying another entire copy of the game seems very wasteful..)

Alright, Where what you do. It will take some work on your side.

What you need should be local:

• one bag for each scenario one that can not be seen through. Easy to get just like a token bag.
• Shape puncher it need to be a good size. I have a 1 inch hole puncher and got it at meijer.
• get a foam sheet. The important thing is a thickness of 2mm.
• glue - stick or spray.
• card stock.
• flat surfaces and heavy objects, like a book.

steps:

1. Glue the the card stock to the foam sheets. Some foam sheets have the adhesive on it. Make sure the card stock is smooth on the foam shear
2. place between flat surfaces and heavy objects on top for glue to dry.
3. Use shape puncher to get the shape.
4. Write monster name on shape and use the shape as a token for the monster and make a monster bag. My would be about the size of the in-game tokens.
5. use the monster cards as references.

Improvements:

You can print on the card stop before. This could included the information about the monster if it fights.

You can glue card stock to both sides but it is harder to make sure both images are where they are to be. It can be hard to get through the shape puncher. It can be hard to glue one after using the shape puncher.

If I would do this and make it the best I can:

I have some coin protectors I use to protect in-game tokens. Since my shape puncher make is holes the size of shape of the token then I would glue the foam sheet to a card stock sheet with some printing on it but only one side. Then use the shape puncher on another printed sheet. Lastly place the them into a coin protector.

Edited to add:

If you want cards then I have a work around for that as well.

I'd simply suggest to scan the cards and reprint those

4 hours ago, Julia said:

I'd simply suggest to scan the cards and reprint those

Agreed, unless you find someone who is going to sell out just that part from their copy then you probably aren't going to find another way besides this. FFG does not sell separate components. Maybe sort your monster deck by type?

Also, keep in mind that the monster deck is not static: scenarios instruct to add monsters either by name or by type. So, if an expansion adds a new Nightgaunt, and you have a scenario saying "gather all the Nightgaunts", that Nightgaunt is added to. At this point, you'd be forced to get multiples of monsters coming with expansions too, and it's simply becomes impossible to keep track of it (even financially)

23 hours ago, Julia said:

Also, keep in mind that the monster deck is not static: scenarios instruct to add monsters either by name or by type. So, if an expansion adds a new Nightgaunt, and you have a scenario saying "gather all the Nightgaunts", that Nightgaunt is added to. At this point, you'd be forced to get multiples of monsters coming with expansions too, and it's simply becomes impossible to keep track of it (even financially)

Of course another thing I didn't even think of until now is that FFG is known for having multiple keywords on cards, so categorizing them would be even harder.

I think I will be doing my ideal anyways. I think it would be easier to move tokens around the board than those cards.