Can I bring a
No, you can’t bring “a.”
Can I bring a bullet but not a gun?
Can I bring a pencil and paper? Or can I only bring the pencil?
Can we only bring things with 5 letters?
Hey wait a minute
Yeah, you solved the riddle. Now you can make up your own riddle, or you can forfeit it and I’ll make a new rule.
You can bring the paper, but not the pencil.
You can’t bring either a bullet or a gun.
The riddle has been solved by @Unlucky !
WE DID IT LADS WE WON
THE FORT IS OURS
Technically it’s a picnic, not a fort 
Sorry I just had the intense urge to be a napoleonic Scottish soldier
surely people will get this one
This time around, you can bring…
What is not blue, though you may bring blue
Truth, yet not a truth, lies, yet not a lie
Everything, nothing, and something
The old and the new, the cold and the hot, but not what’s there and what is not.
Is it opposites?
loud incorrect buzzer
though you may bring that if you would like
Can I bring a potato
No! What is wrong with you? A potato? In my picnic? Unbelievable.
Can I bring TWO potato’s
Can I bring a kitty
no.
Can I bring water?