Is it possible to make a list of all the monsters used in an adventure? I am looking to prepare for TOA, and will be digging through my token collection and adding some homemade ones for any that are missing.

You can do it now, click Monsters on the top, advanced filtering, click sources and Tomb of Annihilation.

Do note that list isn't 100% accurate. It doesn't take into account any of the monsters spawned by the Kobold Inventors.

Quote from JRedmond >>

You can do it now, click Monsters on the top, advanced filtering, click sources and Tomb of Annihilation.

Yeah, I also noticed that it doesn't list the Zombies that the Zombie T-Rex coughs up every round.

Quote from ratwhowouldbeking >>

Quote from JRedmond >>

You can do it now, click Monsters on the top, advanced filtering, click sources and Tomb of Annihilation.

 That will show monsters presented in Tomb of Annihilation, but not Monster Manual creatures used in the adventure.

Yep, I tried that too, it may be worth asking to be added as a feature. In the past when running a pre-generated adventure I made a full list of all the monsters and basic stats and printed them all off made very simple for tracking hit points. And much less having to flick through books lol.

At least Beyond means less flipping through. I usually prepare for my next session by opening a browser tab for each monster the party is likely to encounter, and use a doc with party initiative to keep track of monsters' place in the initiative and their HP.