Just beat the king! The game is real' fun, and milkman×bigbone is the funniest thing. Also, the ability to use skelefriends abilities as long as you pause when they die is nice, it feels good to utilize, and helps make the enemy snipers feel less unfair (due to their lucky snipes).
On the line of enemy snipers, they're probs the best balanced unit in the game, or at least a necicary part of lategame. They help teach you not to do unwinable stuff like archer-spam (based in to much rng so never feels good to play with) and the abuse of low level/hp dudes like nurse or the knifedude (helping you develope different strats and value more towers roles). The ability to remove their bows with curse is nice, same for enemy sheilds.
My favorite strats would have to be milkman×bigbone (THE POWER!!), bard×sillyskull (bonezone💀), and sheildubus×farmer (all yr brianz r belong 2 uz).
Keep up the good work!