The blob of gelatinous muck is a creature in the Spaceman Spiff universe that appeared in a single Sunday Strip. It was encountered on a "distant world" with a noxious atmosphere by Spiff, and manifested hostility by trying to eat him. As per usual, Spiff's weapon (here referred to as the "Blaster") proved useless against the otherworldly nemesis.
Notes
The blob was, in real life, lunch room tapioca.