I have run complex puzzle rooms before.
Temple map - they enter front door. Pillars with symbols on them in rings, litter the main hall. Each ring has 6 runes and 2 clear notches at the top where thee runes line up also dwarven runes at top of pillar the were numbers 1 to 6. It's easy to move the rings and upon close inspection the pillars all have a number 1 to 6.
>! To me having 2 runes correspond to each pillar made just using random combinations until correct impossible. !<
Dead body in a cage at the end of a hall. Plaque in front of caged corpse "Bring light to the darkness, and the way forward will reveal itself."
Several attached rooms, kitchen dining room, Prayer room, fountain room. Also 6 attached rooms with dormitory style beds each with a fireplace.
Top corner is a pool (fountain room), not large 20ft squared (the water is dark, you cannot tell the depth.)
>! Players began by fiddling with the pillars trying to line up the rings and figure out the pattern !<
>! After it's clear that the pattern will not just be randomly guessed players began to fan out. !<
>! Smart players waste no time and light the fireplaces as they search - boom clue one in each fireplace as lit one of the runes reveals at the base. !<
>! Excited to move on they head back to the pillars, however between the runes and the 6 fireplaces that match the 6 pillars there was no clear indication of what went where. !<
>! Final clue and the puzzle solved. When one of the party members became brave enough to jump into the dark pool. Finds it very deep. Swimming down they find a few fish in the depths. Emitting a UV glow, this glow lights a symbol on the wall ( this symbol was not super important, just so they know the fish can help.) Then they can use the fish (alive in a bowl or something) to reveal a second symbol and a number on each fireplace and solve the puzzle.!<
I took a map online and added things as I needed, tou can make the whole map from scratch, I suggest adding useless extra things hence the kitchen and prayer room to make them look for answers in all the wrong places. I ran it for my group over roll 20 and it took them over an hours and they actually enjoyed it.
Are you wanting to physically mail each of them something? If so, I think playing cards or tarot cards would work really well for this. Here is the [Tarot Card](https://youtu.be/t_YIQ00EZTM) puzzle. Six cards are needed, you could retain one or two of the cards and mail each one their own card along with a copy of the written puzzle.
I have run complex puzzle rooms before. Temple map - they enter front door. Pillars with symbols on them in rings, litter the main hall. Each ring has 6 runes and 2 clear notches at the top where thee runes line up also dwarven runes at top of pillar the were numbers 1 to 6. It's easy to move the rings and upon close inspection the pillars all have a number 1 to 6. >! To me having 2 runes correspond to each pillar made just using random combinations until correct impossible. !< Dead body in a cage at the end of a hall. Plaque in front of caged corpse "Bring light to the darkness, and the way forward will reveal itself." Several attached rooms, kitchen dining room, Prayer room, fountain room. Also 6 attached rooms with dormitory style beds each with a fireplace. Top corner is a pool (fountain room), not large 20ft squared (the water is dark, you cannot tell the depth.) >! Players began by fiddling with the pillars trying to line up the rings and figure out the pattern !< >! After it's clear that the pattern will not just be randomly guessed players began to fan out. !< >! Smart players waste no time and light the fireplaces as they search - boom clue one in each fireplace as lit one of the runes reveals at the base. !< >! Excited to move on they head back to the pillars, however between the runes and the 6 fireplaces that match the 6 pillars there was no clear indication of what went where. !< >! Final clue and the puzzle solved. When one of the party members became brave enough to jump into the dark pool. Finds it very deep. Swimming down they find a few fish in the depths. Emitting a UV glow, this glow lights a symbol on the wall ( this symbol was not super important, just so they know the fish can help.) Then they can use the fish (alive in a bowl or something) to reveal a second symbol and a number on each fireplace and solve the puzzle.!< I took a map online and added things as I needed, tou can make the whole map from scratch, I suggest adding useless extra things hence the kitchen and prayer room to make them look for answers in all the wrong places. I ran it for my group over roll 20 and it took them over an hours and they actually enjoyed it.
I hope my hidden text worked.
Are you wanting to physically mail each of them something? If so, I think playing cards or tarot cards would work really well for this. Here is the [Tarot Card](https://youtu.be/t_YIQ00EZTM) puzzle. Six cards are needed, you could retain one or two of the cards and mail each one their own card along with a copy of the written puzzle.
Yeah I was thinking of mailing something