Gloomhaven: Buttons & Bugs is a solo game, with an original campaign written by Isaac Childres, that offers a playstyle similar to Gloomhaven but at a fraction of the size.

Gloomhaven: Buttons & Bugs takes place after the events of Gloomhaven and Forgotten Circles. The reclusive Aesther Hail has built a reputation for her crucial role in saving the city, and she absolutely hates it. Wannabe heroes are constantly invading her studio at the Crooked Bone, looking for help to become famous themselves - and then there are the demons out for revenge. She briefly considered moving, but since that would require effort, she instead placed an enchantment on her front door: anyone who tries to open it will be reduced in size and therefore no longer a problem.

Your character is such a wannabe hero. In an ill-conceived attempt to become famous, you try to visit Hail, and poof. Now you are as small as a mouse and have entered a completely different world of lawlessness. They must find a new way into the Crooked Bone and convince Hail to return them to their previous format.

Each scenario is a single map, pitting one mercenary against a handful of enemies using simplified actions and artificial intelligence. Each mercenary only has four double-sided cards in their hand, but these can be used twice - both front and back - before being discarded. Attacks are resolved using a die in combination with a modifier table, and both the table and the mercenary's skill cards can be improved as you level up throughout the campaign.