Zero Armstrong is one of the main protagonists and a part of the main group of survivors throughout the series.
He is Akai and Arron's childhood best friend and would do anything to keep them safe. He and his friends are traveling from Emon to Lans in hopes to find shelter at a monster lookout camp from the war taking place in hope to find his father.

Bone attacks:
He can summon bones to his enemies with. Sometimes, he even uses a bone to act as a spear.

Yellow bones:
Yellow bones are similar to other normal bones, but the only difference is that whenever a yellow bone hits a wall, it will bounce back and be sent right back. Yellow bones can also change directions when they get send towards a target (similar to Undyne’s yellow spears).

• He loves taking care of flowers, but doesn't want to admit it.

• Zero has a develish smile when he's angry or nervous.

• His mother passed away when Zero was around 5 years old due to an illness that was running through town at the time.

• Zero and his father took Akai and Arron in for a few years. They also taught them the basics of the Windar language.

• Zero has trust issues.

• Zero idolizes Kay, one of his father’s comrades.

• His eyes are yellow because it’s the colour of his magic.

• Apparently, skeletons with yellow magic are extremely rare.

• Zero canot use telekinesis (Blue magic) like how Sans and Papyrus can in Undertale.

• He himself and Ray are the ones who taught Akai and Arron how to use magic.

• Zero is shy around girls around his age.