Phantasm II

Picking up where the first film left off, the Tall Man and his minions attempt to kidnap Mike, but Reggie manages to save him by blowing up the house. Six years later, the film introduces Liz Reynolds, a young woman whose psychic bond to Mike and the Tall Man manifests in the form of prophetic nightmares. Liz pleads for Mike to find her, as she fears that when her grandfather dies, the Tall Man will take him. Mike, who has been institutionalized after the events of the first film, fakes his recovery to make contact with Liz. When Mike returns to Morningside Cemetery to exhume the bodies of his parents, Reggie interrupts him and explains that the earlier attack never took place. However, Mike reveals the coffins are empty and urges Reggie to help him hunt down the Tall Man. En route to Reggie's house, Mike has a premonition and frantically tries to warn Reggie seconds before an explosion kills Reggie's entire family. Convinced by Mike's futile warning, Reggie agrees to accompany Mike. They break into a hardware store and stock up on supplies and weapons. Traveling country roads, they encounter abandoned towns, pillaged graveyards, and a few of the Tall Man's traps; one is an apparition of a nude, deceased young woman. The clues lead them to PÃ©rigord, Oregon.
Meanwhile, Liz's grandfather dies, and her sister Jeri disappears during the funeral; while searching for Jeri, Liz finds the Tall Man and flees. The presiding priest, Father Meyers, maddened with fear and alcohol withdrawal, desecrates the grandfather's body with a knife in a desperate attempt to thwart its reanimation, but the corpse rises and kidnaps Liz's grandmother. In the morning, Liz finds a funeral pin in her grandmother's empty bed, and the Tall Man psychically tells Liz to return at night if she wants to rescue her grandmother. Prior to their arrival in PÃ©rigord, Mike awakens to find that Reggie has picked up a hitchhiker named Alchemy who eerily resembles the nude apparition. They find PÃ©rigord deserted and decrepit. When Liz arrives at the mortuary, she is confronted by Father Meyers, who tries to convince her to escape with him, but he is killed by a flying sphere. She encounters the Tall Man and discovers that her grandmother is now one of his Lurkers; she flees and runs into Mike in the cemetery. Later that night, the Tall Man captures Liz and drives away in his hearse; Mike and Reggie chase after him. After the Tall Man runs them off the road, their car explodes.
At the crematorium, Liz is taken to the furnace room by the Tall Man's mortician assistants, but she escapes and sends one into the furnace. Mike and Reggie break into the mortuary and find the embalming room. While Reggie pours acid into the embalming fluid, Mike discovers a dimensional portal that requires a sphere to open. They then split up to find Liz. Reggie searches the basement, where he fights off a Graver and several Lurkers with a chainsaw and quadruple shotgun. Mike saves Liz from a silver sphere, and, when it becomes embedded in the wall, they use it to access the portal. Before they can destroy the building, the Tall Man surprises them, but they fight him off and pump him full of the acid-contaminated embalming fluid, which causes him to melt. They set the building on fire, escape, and are greeted by Alchemy, who has procured an abandoned hearse. As they ride off, Alchemy reveals herself to not be human, and the hearse swerves wildly, then stops. Reggie, bloody and battered, falls to the ground; Mike and Liz, trapped in the hearse, try to convince themselves that this is all just a dream, but the slot to the driver's cabin opens and reveals the Tall Man, who tells them, "No, it's not." Hands break the rear window and pull Mike and Liz through it, mirroring the ending of the first film.

Question: What does Mike do at the mortuary?
Answer: Discovering dimensional portal that requires a sphere to open