--to complement the new experience scaling system, I've added a new tag to the game that you can use to silently level up generic enemies to a specific level as soon as they spawn: LevelUp. The LevelUp tag takes one parameter: a positive integer that tells the game how many levels the tagged character should gain.
For example: the main campaign has a generic level 1 enemy named Bloodbeard's Bandit. But suppose I want the player to face a slightly tougher version, one that will give him or her more experience points? I can use the LevelUp tag for that. This will level up the bandit twice, causing the player to face a level 3 bandit:
<Unit tag="Add,LevelUp,2">0,1,Bloodbeard's/Bandit,1,17,Down,25 Coins</Unit>
There are two big things that distinguish this from leveling up via the GiveExp script action: (1) it goes right in the Unit tag, so you can apply it to characters that don't have unique names; and (2) it levels them up quietly, meaning you aren't going to see a bunch of experience bars and pop-up text over the enemies at the start of every battle.