Obtain by using Last Shard on Sans.
This stand has a one shot move, and is incredibly rare. The only way to bypass his dodge is to have Hyper Sonic and certain other stands.
Controls:
E - [Barrage] 60.5 to 70.5 damage per hit
R - [Force] 21.4 damage to surrounding players
T - [Bone shoot] 58 damage per hit (3 seconds cooldown)
LMB (click) - Gaster blaster 20 damage per hit
F - Large version of click (Lasts for 3 seconds) (deals 120 per 0.1 seconds when hit) (Instant kills almost every stand.)
Z + Hold - Gaster Blaster Ride (8 seconds cooldown and hovers, flings when hits obstruction)
C - Instant teleport almost spammable (2 seconds cooldown)