Read more about Blackbriar Thorn at: Wikipedia

Official Site: DC Comics

Blackbriar Thorn is a DC Comics supervillain. Created by Len Wein and Joe Kubert, the character first appeared in DC Comics Presents # 66 (Feb 1984).

Blackbriar Thorn was a High Priest of the ancient Druid of Cymru. While his entire sect is massacred by attacking Roman forces, Thorn absconds to the surrounding forest. Attempting to escape capture, he transforms himself into solid wood, hiding amongst the trees. Unfortunately for Thorn, the agony of his dying comrades creates a geological upheaval which buries his newly arboreal form underground.

Millennia later, Blackbriar Thorn's body is unearthed by an archaeologist and subsequently displayed at The Gotham City Museum of History. When moonlight strikes the statue on the night of its unveiling, Thorn is revived and begins to wreak havoc upon the Museum and its patrons, counted among whom are alter egos of Superman and Etrigan the Demon. The mismatched heroic pair's actions drive Thorn to retreat into the city, where he later rampages in a plot to procure a new body—that of Superman. Together, Etrigan and Superman defeat Thorn, ostensibly rendering him incorporeal.

Blackbriar Thorn appears, seemingly in human form, during the Crisis on Infinite Earths. He, Etrigan, and other assembled mystics lend their combined energies—channeled through Doctor Occult and Green Lantern Alan Scott—to successfully defeat the Anti-Monitor's Shadow Demons, which had been ravaging the Earth.

Blackbriar Thorn has not been a contender in any CBUB matches.