The following events were published by DC Comics in the year 1988. This does not necessarily indicate that these storylines took place in the year 1988. The passage of time in the DC Universe is nebulous and subject to change and interpretation. Events from historical time periods are indexed under their corresponding years.
The Fashion Thing begins referring to herself as the "Mad Yuppie Witch".
Millennium: Herupa Hando Hu and Nadia Safir come to Earth to select ten Chosen Earthlings to lead humanity into the next millennium. The super-heroes of Earth agree to help them protect these Chosen. Opposing the unification of the Chosen is the ancient secret society the Manhunters. Note: All events related to Millennium were published from January-February of 1988.
Doctor Helga Jace reveals herself as a Manhunter agent. She brainwashes Metamorpho into betraying the Outsiders. During the fight, Looker manipulates Metamorpho into attacking Jace. She fires a laser weapon at him that interacts with his composition creating an explosion that kills Jace.
An ancient Atlantean Wizard, the Weaver, decides to avenge himself against his old foe Arion, by striking out his (perceived) granddaughter, Power Girl. He sends an agent named the Force after her, but he fails to defeat her.
September 14th: Elderly occultist Alexander Burgess accidentally breaks the mystic ward that has held Dream imprisoned for more than 70 years. Now free, Dream torments his captor with the curse of Eternal Waking. Note: Although published with a Jan-89 cover date, this event actually takes place in September of 1988.
While investigating a string of bizarre murders in Gotham City, Batman is infected by a group of spores from the Grey. He goes missing for several weeks and eventually turns up in Louisiana. He encounters the Swamp Thing who purges the spores from his body.
Jimmy Olsen goes undercover to infiltrate Fate Eddie Cortes' drug cartel. Fate Eddie learns the truth about Jimmy and leaves him to drown in the flooded bowl of a derelict. Jimmy uses his signal watch to contact Superman to rescue him.
Cosmic Odyssey (Dec-March '89): The Anti-Life Equation develops sentience and splits into four equal parts. Highfather of New Genesis and Darkseid of Apokolips form a temporary alliance in order to gain control of the fractured aspects. The Anti-Life Equation evolves into the Anti-Life Entity.
Checkmate begins investigating a counterfeiting ring who have stolen printing plates from the Treasury Dept. They send Knight Roger Dayton to track down and destroy the counterfeiters stronghold, but he runs into trouble when he tackles a muscle-bound criminal named Claymore.
The Swamp Thing attempts to avenge himself against Lex Luthor for "killing" him and attacks Lexcorp Tower. Superman confronts him and convinces the Swamp Thing to let the human authorities deal with Luthor.
Invasion: The Dominators send an alien scout named Widowsfeed to capture the pregnant Abigail Holland. Widowsfeed has a change of heart and decides to let Abby go. Guy Gardner arrives and blasts Widowsfeed's ship out of the sky, apparently killing her.