It's an Elite. So pets will ping it, despite being in desert. Ive found one spawn. 204/294 DK takes a minute or 2 to kill, charge has a knockdown, but minimal damage is taken.

Not my video, but this shows you where to find Kreator. https://www.youtube.com/watch?v=F_9-m4U38Lk

Get Kreator to 50% hp and wait, and he will spawn one Kalten and one Alten. Simply wait for him to dash away and kill Kalten and Alten until you have the desired knowledge. If you don't get the right knowledge, run away and he will reset (he burrows under the ground back to his spawn point back to full HP).

When going for Kreator knowledge he respawns fast so use guild channels to hop between and you can get the knowledge easily.

I was 300AP doing this and I did not one shot him, if this helps anyone.