Hands are one of Gaster's primary weapons. Gaster developed his own fighting style, causing him to summon up to 7 hands under his control, each one with a different power.
- Monotone: All the hands turn of a certain color, amplifying the power of his next attack by 7.
- Red Attack: Shoots a blast of energy, twice as powerful than normal Gaster Blasters.
- Green Attack: Gaster's hand can spawn a forcefield or a shield to protect someone, however it drains his energy the longer he uses it.
- Orange attack: This specific hand has the ability to spawn white dots around their enemy, when the dots turn orange they create a deadly explosion.
- Blue Attack: Gaster's hands has the ability to spawn up to 2 blue razor blades in a disc that follows its enemy.
- Yellow Attack: Gaster has the ability to turn one of his hands (or both when using Duality) yellow, this shoots projectiles at a really fast pace.
- Purple Attack: This ability is able to copy anything in front of this hand (the purple one in this case) and be able to copy it’s exact power aswell, but it is likely to get destroyed if it is overwhelmed with too many powers.
- Light Blue Attack: This hand has the ability to shoot up to 4 that stick to its objective until Gaster decides to let go, or the string is cut.
- Gaster has holes in his hands. He uses them for controlling and using his powers.
- Since Gaster has really unique powers, the holes in his hands get filled according to the power he’s using. So he can actually shoot powers from those holes and also shows what he’s using, he kinda was born with that.
- His perseverance power is blocked and he was only able to use it in Yet Darker due to ”weird void powers”.
- Every power that Gaster uses actually represents each one of the human soul traits.
- Hands' color/attack can be the same if Gaster wishes so.