Ivan's first sign of betrayal: oozing Rita's mouth shut. Even Zedd praised him briefly for that.
Dulcea appearing and taking out the Tengu Warriors.
Fred, who'd been spying on Ivan Ooze for a good part of the movie, revealing to the kids of Angel Grove that Ivan has ordered their parents to take a fatal dive at the construction site and convincing them to go help him intervene. The kids eventually make it to the site just as their parents are approaching a steep drop and start pushing them back—however, many of the kids aren't strong enough to stall the adults, so Fred, Bulk, and Skull commandeer a nearby high-pressure water cannon to buy them some time. They manage to last until the Power Rangers finally defeat Ivan, breaking his hold over their parents.
On a related note, Tommy gets a moment near the end when he uses his Zord to bridge the gap in the monorail track that Ivan destroyed a part of, saving the kids using it from a fall.
Tommy's incredible dropkicking skills, both in and out of the suit. On the first occasion, he flies horizontally towards an Ooze Mook and kicks him dozens of times with each foot, finally booting him towards a wall and pulverizing him to slop. The second time he pulls the "Ninjetti Corkscrew Kick", flying towards a gargoyle while spinning corkscrew style and dropkicking him towards a wall and his disintegration.
If there was one ranger that got to finish off Ivan it was Aisha and courtesy of a groin attack to knock him into a comet.