It's not as impressive as SotN. In SotN, experience gained halves every level, which was the reason I could RUN from boss to boss, skipping most enemies, barely survive, and continue thus all the way to the Schmoo, where I'd hunt casaggargasssaamagaien. I think my all-time highest level in SotN was 77, achieved by taping down the shoulder button - with the buttons reconfigured to make that the shield button - and equipping the Medusa shield, then standing in front of spawning zombies and letting the system run for a week or so. Around level 60 Final Knights become worth 1 xp, so it's literally a better idea to level off zombies. And the XP requirement for each level goes up in a parabolic curve.
Of course, after level 35 or so you'd have to be retarded not to be able to beat SotN.
In Ecclesia, experience gained ranges from 1 (bats) to 400ish for really hard enemies (final knights) and you can keep getting 400 xp from them no matter what your level. The XP amount for each level ranges upward, but not all that quickly. I'm pretty sure it won't take more than five or so hours of work to get to level 255.
The most impressive thing in that screencap is the number 65535 next to the seven pink symbols.