"Death at the Dawn of Time" by Marv Wolfman, George Perez, and Jerry Ordway.
The Phantom Stranger gets a little more to do in this issue, bonding with his fellow magicians (Dr. Fate, Madame Xanadu, Zatanna, Sargon, et al) to help transfer their powers to The Spectre, so he has enough strength to take on the Anti-Monitor:
This issue is a little better for us PS fans, since he actually gets a line this time. Two, in fact!