A centennial is a 100 year anniversary or otherwise relates to a century, a period of 100 years.
Notable centennial events at a national or world-level include:
Centennial Exhibition, 1876, Philadelphia, Pennsylvania. First official World's Fair in the United States, celebrating 100th anniversary of the signing of the Declaration of Independence in Philadelphia. About 10 million visitors attended, equivalent to about 20% of the population of the United States at the time. The exhibition ran from May 10, 1876 to November 10, 1876. (It included a monorail.)
Caber is one of the Celtic gods of Avalon, a warrior god. The character, created by Tom DeFalco and Ron Frenz, first appeared in Thor #398 (Dec. 1988).
Caber joined his friend Leir and the other Celtic gods in aiding the Asgardians in their battle against the forces of the Egyptian god Seth. With Leir, Caber next attacked the camp of the Fomorians, the traditional enemies of Avalon. Leir wished to claim Sif as his bride, so Caber followed him to Asgard on Leir's request. Caber and Leir were captured by the Warriors Three. Caber clashed with Heimdall in Asgard, and then later arrived on Earth with Leir and Sif. Caber, Leir, and Sif then traveled to the Black Galaxy and found Thor there. The gods then traveled to Asgard. Caber, Leir, and Hercules then battled Surtur and Ymir. Caber then witnessed Leir's defeat in Leir's duel with Sif.
Caber possesses the typical powers of a member of the race of superhumans known as the Celtic gods of Avalon. This includes superhuman strength, speed, durability, stamina, and reflexes, and an extremely long lifespan.