Defensive Theatrics.

[Adoede]

There are a few things that effect surprise ending rates. That said, most of the fun of this game is in figuring out those little details yourself so without giving away too much, I will say that there are definitely things you can do to make "Surprise Ending" a more consistent part of your strategy. Running a good defensive strategy certainly helps. Stat distribution also is highly important...though perhaps not the stats you'd expect. Combat effects like "Entangle" that reduce enemy effectiveness also boost surprise ending chances. Your defensive prowess vs. opponent's attack power also factors.

Watch glads who use surprise ending effectively very closely and you should start to see some patterns. If you build it right, you can have a glad who throws surprise ending in every fight and even multiple times in a single fight. I've even seen some Theatrics surprise ending every single attack of their opponent during an entire match...granted their opponents didn't attack much...