Runes after level 50.

[Specaz]

i maxed trap medal with skald quite easy (on imposible). It's so easy to bait them with summons or low level units (draids -> thorns in my case). And you have a lot of tools to get enemy at low health: same sumons (thorns can make 1/2 stack of their size, and so on), different level rage skills, so you adjust their total life with it, and then bait. It gets easier after 2lv medal, because of +% trap damage.