Part 1 deals with incorporating riddles into an adventure whereby the solution is specific to the adventure. Part 2 is more generic, providing riddles for general use as opposed to a specific use. Part 3 talks about finding new riddles and even provides a way to create your own original riddles.
Here are some general riddles. I have no specific ways to use the answers, but these can still be used during an adventure. The answers may need to spoken aloud to open a door, or reveal something hidden within a room or to unlock a chest.
An interesting idea would be to have a consulting mage that the characters need some information from, only he will not see them until they can answer some of these riddles first as a test on their intelligence.
If the characters ever need to have a compatriot raised from the dead, the clerics they go to may be willing to do so, but first the players must answer the riddles that have been presented to this church by the followers of another deity, a goddess of logic, magic or intelligence.
A town may be holding a faire this week and a riddle contest is one of the diversions. The characters could enter for fun or for the large purse reward for the winner.
A) I am strong in the river. I can make you shiver. Small and off the vine. I’m now this moment in time.
B) The first two letters, signify a male. The first three letters, signify a female. All four letters, signify a brave person.
C) She has one. A person has two. A citizen has three. A human being has four. A personality has five. An inhabitant of earth has six.
D) The answer is not as jumbled as this: SACKTE; but the meaning is the same.
E) IT CUTS
The answer is at the end
F) No legs to dance with. No lungs to breathe. No pipe to smoke. And yet it does all three.
G) When boiled, this is hard to beat. It must be stripped, in order to eat.
H) The first is in cook. The second in shallot. The third is in cheesecloth. And the fourth is in soufflé.
I) A precious gift, yet it has no end, no beginning, and in the middle, nothing.
J) I can run but not walk. Wherever I go, thought follows close behind. What am I?
K) You use a knife to slice my head and weep beside me when I am dead. What am I?
L) I'm the part of the bird that's not in the sky. I can swim in the ocean and yet remain dry. What am I?
M) Weight in my belly, trees on my back. Nails in my ribs, feet do I lack. What am I?
N) As a whole, I am both safe and secure. Behead me, and I become a place of meeting. Behead me again, and I am the partner of ready. Restore me, and I become the domain of beasts. What am I?
O) What is put on a table, cut, but never eaten?
P) What kind of room has no windows or doors?
Q) A kind of weather that comes your way, but add a “D” and it will run away.
R) When you need it you throw it away, but when you don’t need it, you take it back.
The answers to the preceding riddles follow now. If you need more time to try and figure out the answers yourself, I don't recommend scrolling down further yet.
O) Deck of cards