Tonton Streaming Extreme Ghostbusters (1997) S1E23 - Slimer's Sacrifice

Slimer gets trapped in the containment unit (and Peter Venkman isn't even here to see it), surrounded by some very vindictive ghosts that remember him, including a demon named Surt who wants to bring about Ragnarok. Eduardo goes in to save Slimer, while the rest of the EGB has to bust a demon hound in the Firehouse.