As a Vanar player I personally find that the Infiltrate mechanic is too limited an thematically out of place. Infiltrate as a mechanic is only useful on one half of the game board. Compared to the other factional mechanics it seems to have the least capability or ways of achieving its goal. It is weak to rush as a mechanic an demands a specific play style to be successful. Thematically it seems like it should belong to the Songhai faction as they have the mobility tool to get the most benefit out of a mechanic of that nature. So why not Frostbyte. Frostbyte fits both thematically and removes the half board weakness of infiltrate.
Frostbyte -
Whenever this card deals damage to an enemy minion with more health than it, it will stun it.
OR
Attacks made against this card reduce the damage dealt to it by (X)
Perhaps this mechanic is too strong but, I wanted to open the discussion.