Ok, so I am by no means a high level player, working around 2500 trophy range (fluctuates) at level 63. I seem to have days that I just own everyone other king I come across and other times I cant seem to beat a level 10 king.
This is my general set up:
Knights - usually have them boosted and zerg
Cannons - obvious tower damage
Mortars - cause most defenses I see have mostly paladins and arblasters in their waves
I exchange the mortars based on what I see in enemy waves, but like I said above seems most used defense units are weak to poison
Firestorm - help kill firebolt towers and decent troop killer
Swordrain - kills about anything but paladins in one hit
Shield - just like it more than heal
I do exchange spells depending on the towers and waves I see sometimes, but the above is what I use the most.
Now my strategy that I have that seems to work best (for me so far) is that I let my knights and cannons take care of towers while I take out the waves. This is hit and miss sometimes as the cooldown on spells is over my spells, but I messed around with hammerstrike and it just didn’t seem to have the desired affect. I have tried several different strategies and this has been the best for me so far, but I want to try new things and see where it can take me.