Lord of Mossflower
The Lord of Mossflower was a gigantic pine tree, standing out in the middle of nowhere. It existed during the time of Abbess Germaine, as she mentioned it in a riddle that provided directions to Loamhedge Abbey. Seasons later, Matthias encountered it while trying to find Loamhedge.
However, many generations from that time, the Lord of Mossflower had either fallen or been cut down, and what was left of it was used as a solid bridge across the abyss. It was then levered out of place by Bragoon and Sarobando during the Battle in the Abyss, allowing their fellow questers to return to Redwall Abbey safely. It fell into the abyss and was never seen again.