Each player should get 3-4 wall sections that look normal but when anything jumps over it it either blows up or acts like a spring trap and eliminates the troop from battle or Another thing it could do is freeze all troops within a tile range and any troops that come in to that tile just like the freeze spell. It is almost impossible to stop a hog/gowipe attack when they use a high number of hogs or Golems and spells. Weapons barley have time to get off a shoot or two. I for one have spent many hours upgrading my base and troops. Bombers go through my million dollar wall sections the same as they go through level 1 walls.
Each wall all section could be upgradable to x level = to freeze spell. Once one goes off that is it for the battle the other 2-3 sections will not go off or allow all of them to work too. Air attacks would not be affected although it would be nice to have a freeze weapon that can shoot at air troops too.
Sorry i i don't know all the hit point stuff that would need to be up to the game programmers to figure out. The possibilities are endless what the wall section could do
Wall section level 1 spring trap effect Wall section level 3 uses fire / electric shock
wall section level 2 blows up / shoots Wall section level 4 freezes
Thanks for your time
PapaBuck



