After fighting through some high-powered aliens and getting Zexonyte, Dr. Andonuts is able to fix the Phase Distorter.
Give Dr. Andonuts the Zexonyte
Use the Meteorite piece on Dr. Andonuts in Saturn Valley. Then rest in the hotel, and the Phase Distorter II will be ready in the morning.
When you go into the Phase Distorter II, you won't be able to go back. Make sure to prepare. Equip everyone with protection from Flash: the Sea Pendant, Night Pendant, and Earth Pendant all protect from it. You should also get Multi Bottle Rockets in Deep Darkness, Super Plush Bears in Summers, and Brain Food Lunches in Dalaam. Also, give Paula the Franklin Badge, and make sure that she is equipped with the Sea Pendant, Night Pendant, or Star Pendant.
If you want to get every possible Photo Man picture, check the Photo Locations page. However, you will still have a chance to get more Photo Man pictures after this.
Talk to Dr. Andonuts when you are ready to go, then talk to him again to confirm that you are ready. Then walk into the Phase Distorter.
Cave of the Past
The Phase Distorter II takes you to the Cave of the Past in the Lost Underworld. After you step out of the machine, you can check on it to heal up and call your Dad.
Go east, and the Star Master will teach Poo PSI Starstorm Ω.
Keep going east and you find a Mr. Saturn next to the broken Phase Distorter that Pokey stole. Check on the broken machine to get a Horn of Life.
Go north to look at the metal tentacle. It doesn't do anything. Go south and the Phase Distorter III will appear. Talk to Apple Kid, then talk to Dr. Andonuts. When he walks away, follow him and talk to him again. Say Yes to his questions. Then when you are in the Phase Distorter, say Yes to activate it.