Prioritize your curve above everything else. The deck is much weaker when you miss King at 6 DON!!. Use Queen, We're Going to Claim the One Piece!!!, and Mamaragan when necessary to find missing pieces instead of holding only your large Characters.
Use the Leader effect both offensively and defensively. The -2K Power can help remove an opposing Character, but it can also shrink an attacker and save Counters. With multiple ways to recover DON!!, DON!! -1 is often less punishing than it looks.
Don't spend Sasaki just for ramp. He is mainly a 2K Counter; his effect costs 2 cards from hand to add 2 rested DON!!. Use it only when you truly have no other way to stay on curve.
Yamato can be used as a Blocker early. Once she has ramped you, her main job is done. Because the list has relatively few conventional Counters, don't hesitate to use her to protect Life.
Usually keep your first Kaido OP17-062 active. His role as a Blocker is often more valuable than an immediate 12K attack. Once you have several large Characters and a stable position, start attacking with him to raise the pressure.
Use Kaido OP17-062 to preserve 2 active DON!!. After using the Leader's DON!! -1, his effect lets you recover DON!! and can leave you with resources for Counter Events, making Slow-Slow Beam Sword far more threatening.
Punish a poor attack order with Slow-Slow Beam Sword. If your opponent attacks with their Leader while a large Character has not attacked yet, Counter the Leader attack and rest that Character before it can swing. To play around it, they generally need to attack with their Characters before their Leader.
Slow-Slow Beam Sword stacks well with the Leader effect. Reducing an attacker by 2K Power and then gaining 2K Counter already creates a major swing, with the option to rest another opposing attacker on top of it.
Mamaragan changes roles over the course of the game. Early, its 1K Counter with Draw 1 at 6 DON!! or less can help you find King. Late, hold it when you can set up the interaction with Charlotte Linlin to rest the Character whose base Power Linlin reduces to 0.
Track the order of your DON!! -X effects. A DON!! returned to the DON!! deck is no longer on your field. Before using several effects in one turn, calculate what King and Kaido OP17-062 can actually recover so you don't compromise your next 9- or 10-cost Character.
Lead Performers doesn't need to be replaced immediately. You can play it to recover a Life, keep it on the board, attack for 11K next turn, and then trash it to play Queen. This lets you benefit from the heal, attack, and replacement.
Adapt your 10-cost play to the board. Kaido OP17-062 is the default stabilizer because of Blocker, while Kaido OP17-063 is especially strong when an opposing Character that costs 6 or less must be removed. His effect that turns Character cards into 1K Counters can also greatly improve a hand full of large Characters.
Keep your small cards relevant in the late game. We're Going to Claim the One Piece!!! remains useful whenever King or Kaido leaves you 1 DON!! available, and Queen can turn unneeded large Characters into fresh cards. The deck has several ways to recycle an awkward hand.