guess what bookapple?
Took me 60 minutes to beat it
I just had to spam doge, wall doge, and angel doge, with the skills as war drum, power up, and lightning strikes.
I alternate between power up and war drum when the boss attacks, regaining land that I lost, occasionally getting him behind the base.
Of course everything I used is max level.
Though it would be nice if you could also obtain the secret cat to assist, because I did this with the secret cat, I hope this helps bro!