[11] Horn became interested in animals at a very young age[8] and cared for his childhood dog named Hexe (meaning witch).

A family friend was the founder of Bremen Zoo, which gave Horn access to exotic animals from the age of 10.

[8] The duo met on board the cruise ship TS Bremen where Horn was a waiter and Fischbacher was performing magic under the stage name Delmare.

[7]: 33  The two were fired from the TS Bremen for bringing a live cheetah onto the ship, but were scouted by a cruise line based in New York and began performing together as a duo.

[12] The owner of the Astoria Theatre in Bremen saw Fischbacher and Horn's act aboard a Caribbean cruise ship and recruited the duo to perform at her nightclub.

[16] In 1990, Fischbacher and Horn moved their show to a newly opened casino and resort in Las Vegas, The Mirage, where they performed until 2003.

[14] During a period of their careers, Fischbacher and Horn were romantically involved, though they avoided discussion of their private lives.

[18] As part of the act, but veering off-script, Horn held the microphone to Mantacore's mouth and told him to say "hello" to the audience.

[citation needed] By March 2006, Horn was talking and walking, with assistance from Fischbacher, and appeared on Pat O'Brien's television news program The Insider to discuss his daily rehabilitation.

[27] In February 2009, the duo staged a final appearance with Mantacore as a benefit for the Lou Ruvo Brain Institute (though Chris Lawrence had stated this performance involved a different tiger).

[31] In June 2016, director Philipp Stölzl announced that Fischbacher and Horn would produce a biographical film documenting their lives.

"[9][33] His condition deteriorated, and he died ten days later on May 8, at age 75 while at Mountain View Hospital in Las Vegas during the COVID-19 pandemic in Nevada.

[34][35][36] The duo's spokesman, Dave Kirvin, announced Horn's death, saying it was due to complications from the disease.