I think as it is now its pretty stupid. The Endboss should be a reward for clearing the wave and filling the Meter up.
As it is now its pretty retrded. If you dont get the Meter up in the same round the boss spawns in the middle of the fight completly fcking up the wave.
for example starting a fresh 20 wave is pretty easy coming from wave 19 to 20 with a half filled meter and getting unlucky that the minibosses spawn all at the end and on top the endboss spawns its absolutley impossible to clear the wave.
pls funcom fix