Okj, I tried some more Sluggish Walls with my dad. We played 15 games. We split them between the 3 factions I thought it would bust - CG, MV, and GD. We played against all the other factions. I played as the wall destroying faction 8 times, and my father, 7. 13 out 15 games, the destroying faction won. And in 14 of those games, all the walls of the other factions were destroyed. (In one game, I overextended with my MV. I killed all of his BD walls, but he had enough crap already out to take me.) It busts those factions horribly. And, even worse, the CG didn't suffer a single loss, and my dad and I suck with CG!

How about this rule, for each wall - If the player did not summon a unit adjacent to this wall this turn, place a wound marker on this wall.

There. Punishes players who spend turns not doing anything. Also buffs wall crowding. But it doesn't allow GD players to blow your wall up on turn two with nothing but their starting setup.