Is it possible to create a custom giveaway url?

It's always random.

it is impossible to make custom url, urll will always contain 5 random digits, you can think of a puzzle while having these 5 digits, thinking how to use them, not other way around.

It's possible, yes - but only cg and the super mod can do it as far as I know - so for all of us normal users it's always randomized.

Yes it is, I remember Rinarin doing just that for a puzzle once. Sadly I think you need to be a super mod to be able to do so.

Yes, it's always 5 random characters

Good to know, thanks.

you can make a lot of GA and hope one of them would be cool...
some times they "spell" soemthing