Hard Riddles With Hints and Answers

I sit in a corner, get cancelled before the journey begins, and may cross oceans stuck to someone else's words. What am I?

Feed me dry wood and air and I grow; starve me of oxygen or give me water and I die. What am I?

In wallpaper I am seen, in a drumbeat I am heard, and in a password I am hunted. Once noticed, I am hard to unsee. What am I?

I am first in end, last in place, and appear four times in experience. What am I?

A diver feels me in deep water, a student before an exam, and a tyre when it is inflated. Too much of me can crush. What am I?

No hands are needed to break me, no box can hold me, and keeping me matters only after I have been tested. What am I?

A bank studies me before lending, a writer wants me after a quotation, and a card can run out of me at the worst moment. What am I?

Lawyers build me, logicians test me, and one weak premise can make me collapse. What am I?

I sit under a conclusion so quietly that people may argue above me for hours. Challenge me, and the whole discussion can change. What am I?

A fence may mark me, a deadline may become me, and a joke may reveal me only after it has gone too far. What am I?

A referee gives me, a court records me, and a crowd may pass me before the evidence is complete. What am I?

It leaves no bruise, yet one remembered action can make it grow heavier for years. What is it?

A sunflower head, a pine cone spiral and the numbers 1, 1, 2, 3, 5 all point to me. What am I?

I can stop a sale, protect a boundary, end a request, or save a life. I am only two letters. What word am I?

Two identical glasses hide me. Fill one a centimetre higher than the other, and I appear. What am I?

At a border I may be crossed; in a queue I may be joined; in a script I may be delivered. Same word, three places. What am I?

The moment I am told, I still exist, but I no longer belong to one person. Add more keepers and I become harder to keep. What am I?

I tell time by copying the sun's refusal to stand still; indoors I am useless, and at noon I almost disappear. What am I?

Move me one place in an invoice and ten pounds becomes a hundred; I look tiny, but I can empty a budget. What am I?

Evidence can open me, fear can close me, and one conversation can change me without touching me. What am I?

I am not written on a CV; comfort may hide me, pressure reveals me, and repeated choices build me slowly. What am I?

A detective may reach me without taking a step, and one false clue can send me in the wrong direction. What am I?

A coin is a circle on the table, an oval from the side, and almost a line at eye level. What changed?

Project managers like me broken into tasks; ignored, I grow costlier; examined, I reveal the next step. What am I?