For example, a customer wants a potion to help them swim in a frozen lake without feeling cold. The party grabs a potion of Diving and a potion of Campfire and combines them to get the effects of underwater breathing and cold resistance. For a sillier approach to that potion puzzle, perhaps they combine a fishy potion and a potion of hot sauce to give the customer temporary gills and a sensation of having their mouth on fire to keep them warm.

Dong, J., Shi, K., Zhang, Y., Tenigeer & Yao, Y. A. Mechanism analysis of ancient Chinese crossbows. Mech. Sci. 11, 437–445 (2020).Rasmussen, P., Zhang, W. & Liu, N. Traditional Chinese Puzzles II (SDX Joint Publishing Company, 2021). Yan, H. S. & Kuo, C. H. Topological representations and characteristics of variable kinematic joints. J. Mech. Des. 128(2), 384–391 (2006).

These valves can be removed and attached to different systems, but the players only have access to a limited amount of them. They must work together to navigate these chambers. They might raise the water levels to push a floating platform up high. They might drain a room of water to allow them to reach a doorway they couldn't hold their breath long enough to get to before. This is a potentially deadly maze if the party isn't cautious with what valves to turn.Yan, H. S. & Kuo, C. H. Representations and identifications of structural and motion state characteristics of mechanisms with variable topologies. Trans. Can. Soc. Mech. Eng. 30(1), 19–40 (2006). Dungeons & Dragons has something for everyone, from those just starting to experts. You can battle monsters, plunge through dungeons or simply hang out at the local tavern. No matter what your players enjoy in a session, it's always good to have variety. As the party navigates a mysterious mansion, they enter a room full of clutter and strange decorations. The ceiling begins to lower slowly. The walls around them begin to move in too. The doors to the room have vanished completely. This is a timed puzzle. They need to figure out how to stop the surfaces from moving in or find a way to survive. There are plenty of solutions you could go with. There could be paintings around the room, showing people in certain positions or interacting with particular objects. This next puzzle would fit well in an Arctic setting but could also fit in any dungeon or tomb your players are exploring. The players must get through a long tunnel, which has completely frozen solid. With their weapons and spells, they can start to chip away at it slowly, but over time it continues to freeze again, putting them at risk of getting frozen in place. As an additional threat, the tunnel is full of frozen monsters that awaken when freed from the ice. This is a fun, simple puzzle you could include in any dungeon or other location where the party gets split up. The rooms that they are in are full of magic, hindering their ability to communicate with one another. They cannot speak directly, but they can still see one another. This might be through a magical mirror on one side of the room, or perhaps some of the party appear as ghostly forms around their friends.