Ice Key / Glass Key

[keen vessel]

These could either be seperate keys, or mechanics for just the ice key

Ice: A key that melts over time once picked up. You have a limited time to deliver it to a lock or lose it. Makers would need to be careful to attach it to respawners to avoid softlocks. You could set it to melt at different speeds, or not at all. Pedastals (or some special cooler box item or something) could be used to reset/pause the timer. If exposed to fire (getting hit by fire, walking too close to torches/fire slimes) could also speed up the timer or melt the key immediately.

A second option could be to toggle if it shatters; This could be delegated to a "Glass key" if giving both settings to one key would be too much. If you take damage while escorting the key the key shatters and you have to go back and get it again. Again, this would need a respawner or special rules to avoid softlocks.

If we cant set specific timers the options would likely be as such; option 1; "melt speed" [X],[1],[2],[3],[4],[5]. option 2; "can break?" [y]/[n]. if we use 30s as the "base" (3) speed, the timers would be 15/22.5/30/45/60 seconds. Double all times if 1m is the base.

[sage dust]

another option to having different timers we can set the key to have could be to have multiple different stages of it melting, with makers being able to place keys down at any given stage
it would provide additional visual feedback to both how much time you will have when you pick up the key in addition to letting you know roughly how much time you have left while holding a key

[keen vessel]

if the key is teeth down, that would be a great visual feedback effect. so, clicking on the key would toggle what stage it starts at?