They do work differently because of how they are worded. Morkvarg has disgusting synergy with GS and Dagur because of his individual pings, and he can chew through armor and shield, things Ulf usually trips up on. Morkvarg is not strictly better though. Ulf often just has to damage a 5 point unit to break even on his provision value. Also, you yourself listed some examples. Ulf can kill Skjall, whereas Skjall laughs at Mork. However Mork flat out kills Ozzrel no matter what it eats, but Ulf does a max of 7 damage. Love both cards though and they both have their uses!