Fast ways to grind out level 40?

[WM0003]

I have finished almost every trophy in the game (minus "I Can Do This All Day" and "Hero of Ostia") and I'm only Slayer Level 36. Are there any quick ways to reach level 40? I know the guide mentions crafting behemoth armor and weapons for quick points and that killing the behemoths 10 times in their armor speeds it up too. But I'm wondering if any new ways popped up since the guide is a little bit outdated. If those tactics remain the fastest how long will I likely have to grind to reach level 40?