Combat: Tether beasts prefer to attack their intended victims from ambush, if possible, but they attack even if they are the ones surprised--or if they're wounded, or being offered an appeasement, or if they're hungry or full. Basically, they are happy to attack anyone at any time for any reason--or even no reason at all.
The tether beast is far and away the fiercest hunter on the Demiplane of Time. It attacks and eats anything it happens to come across, from tempsynth to temporal gliders, and apparently chronomancers rank high atop the list of their favorite foods. A tether beast that finds the silver mist trail of a Demiplane of Time traveler follows it until the trail disappears or the adventurer is found.