This is the second battle of Glitchtale's 1st Season.
After the RESET, Frisk decided to take the pacifist route. When Frisk was visiting Waterfall, Frisk discovered an unknown room, where there stood an unidentified creature, other wise known as Dr. Gaster.
Sans wanted to talk to Frisk about the reset at Grillby's. However, he quickly noticed that Frisk was missing.
After Frisk was trapped in the grey room, Gaster began to attack them several times. However, Sans came in and tried to protect Frisk, but he wasn't powerful enough to stop him. Then, Sans got the idea of absorbing Frisk's soul in order to defeat Gaster. Luckily, Sans and Frisk won the battle, Sans confronted Gaster and told him that killing others isn't the correct answer to get out of the Void. Gaster refuses to listen and attempts to attack Sans from behind, but he is impaled by bones before the attack hits Sans. Gaster turns to Dust and Sans resets the timeline again.
|Pre-Glitchtale Battles||Chara vs Asriel ◆ The Great Human and Monster Wars ◆ Agate Lightvale vs Copper Lightvale ◆ Integrity vs Asgore ◆ Flowey vs Sans ◆|
|Season One Battles||Frisk & Chara vs Sans ◆ Gaster vs Frisk & Sans ◆ Chara vs Sans & Flowey ◆ Chara vs Omega Flowey, Sans, Frisk & Gaster ◆ Asriel vs Chara◆|
|Season Two Battles||The AMD's trap ◆ Battle on The City ◆ Gaster vs Bete Noire ◆ Undyne vs Bete Noire ◆ Frisk vs Bete Noire ◆ Asriel & Bete Noire vs Frisk, Toriel & Asgore ◆|