fxray: whoops, wrong level.
I put one blue mage with Cripple near the center top where both paths of enemies cross. Went the heavy-damage path (Generalism -- Destructor -- Massive Damage). I put red mages near the bottom to mop up any missed enemies, going the heavy-damage path as well.
Odd thing here: on the Forgotten Bridge (15-wave Medium), I placed a mage at the closest available spot to the entry arrow. It had a +1 to dmg from a skill point, and showing a DMG rating of 11, but it was killing 40-HP skeletons with one hit.
Lucky you, fredooi -- I've got all 21 levels (the bonus ones are buggy enough for enemies to disappear if you wait long enough), but the server's been red for me all day, so no final badge for me yet.
It took a number of minutes before my card showed up, after I completed a campaign. I recommend leaving the browser be for a while after completion -- take a half-hour break, do some work ;-)
That's my one big issue -- the reliance on luck to make it through the later levels. Too often I'd be going in circles trying to find an expander to kill, only to have 3 or 4 monsters on my tail with no chance to respond. More map circles would be helpful.
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