Here is a Solo Strat that may help:
Credits to: https://www.youtube.com/watch?v=zQzPU9Cceqk
Towers Required:
Cowboy (Can be Golden) , Commander, Mortar, Pursuit, and Outlaw.
Do all the moves below in order (Recommended Map - Autumn Falling):
Place 2 Cowboys of Level 0 at Start
Place 5 Mortars of Level 0
Place 7 More Cowboys of Level 0 (A total of 9 cowboys)
Upgrade All Cowboys to Level 1 (For Hidden Detection)
Upgrade All Cowboys to Level 3
Get 1 Commander of Level 3 and use call of arms ability when needed
Upgrade All Cowboys to Level 4
Get 2 More Commanders of Level 3 and use call of arms at all times
Get 10 Outlaws of Level 2
Get a Commander of Level 3 for outlaws and mortar
Max out all Motars
Get 10 Pursuits of Max Levels, if you have max towers, sell cowboys
Sell the other 4 Commanders 1 at a time, and replace them with Commanders of Level 3 that cover Pursuits, Outlaws, and Mortars
Max out all outlaws
Max out all Commanders
Sell Cowboys and Move them in range of commanders’ call of arms.
Max All Towers
⭐Please Remember to always use call of arms or it won’t work⭐