Does Nightmare Sans Have Gaster Blasters?

Sans has no Gaster Blasters except for one giant goop-spilling Gaster Blaster. Although its full power is unknown, he usually uses it either when he's bored of his opponent or wants to end the fight very quickly.

Does Nightmare Sans have a weapon?

He can also whisper to people with ongoing negative emotions, as in mind controlling them. He's immune to weapons; if stabbed, it causes no damage and he'll absorb it. If not dropped, the weapon will be trapped in black goop and start to melt. He can also fall/jump from a great height without sustaining damage.

What is Nightmare Sans the guardian of?

When the original guardian of the Tree of Feelings died, Dream and his brother nightmare were created. ... Nightmare consumed the fruit of which he guarded, turning him into an amorphous creature of pure hate, which feeds off the negativity throughout the multiverse.