Im currently a raider leveling in Xita Refuge as level 130.
When a week ago or something a xp boost activated without me realizing.
I got 2-4 percent for killing yellow/red, in Luna (I thought this was normal)
When I got to Xita refuge the xp boost dissappeared without me realizing,until I saw what I got for killing a Pink Monster (a Pincer to be precise which is around 20 levels above me)
But I got 0.5-1% percent per kill. I was really confused until I found out there was a an xp boost.
I just think getting 0.5-1% xp is way to low for killing a monster 20 levels above you.
It would also make the game way more fun since with such low XP gain, it becomes boring quickly.