Horses, and a human found at Mt. St. Jean, and a search of the reverse slope at Waterloo ...
With the pandemic delaying the excavations at the Battle of Waterloo, archaeologists have now returned in 2022 to the site, and begun excavating what is understood as having been the British field hospital at the Mt. St. Jean farm. Besides the human remains of limbs discard after amputations occurred, there have also been found horse (quite the hypothesis in the video on those), and the skeletal remains of only the second human to be be found at the battlefield.
https://www.youtube.com/watch?v=-foPIB4rrJY