Chaos King Fight

Spoilers

The Chapter 1 fight

King waits at the top of Card Castle, at the Eastern Fountain. He grabs Lancer and tells the party to surrender. Lancer gets free, and the battle starts. King says the Lightners abandoned the Card Kingdom Darkners, and that he serves the Knight.

You cannot SPARE him. In DELTARUNE the battle is scripted for 15 attacks and then ends. Dropping his HP to 0 ends it sooner. Talk on Kris, Susie, and Ralsei becomes Courage, Red Buster, and Dual Heal. Courage costs 25% TP and reduces damage by 20% for one turn. Red Buster costs 60% TP. Dual Heal costs 50% TP and heals from Ralsei's magic. This Scratch battle uses the author's Magic, Item, Mercy, Block, and Act labels instead of those three spell names.

If the party has not been violent with other Darkners, Lancer and the Card Kingdom crowd overthrow King after the fight. If they have been violent, Susie distracts him and Ralsei casts Pacify. Lancer's page is the bike battle from earlier in the chapter.

Spoilers

Attack patterns

The wiki says King's attacks move the bullet board, and that they always arrive in the same order. The first cycle is spades, the chain swing, chains, the spiked cage, a faster swing, the chained cage, faster chains, a faster cage, spades again, a faster swing, then the cage with a spade grid. After attack 15 the original battle ends.

• Spades travel from the left or the right. The wiki's dodge is to sit near the center and step up or down when a spade lines up with the SOUL.
• Swing: he chains the board and rocks it while a line of spades crosses. Later swings are faster and the gaps shrink. This one hits the whole party.
• Chains fall along red warning lines. Later chains come faster and warn you for less time. Step a short distance off the line.
• Spiked cage: the cage bounces inside a square of walls. Stay near its center and reverse when it hits a wall. Later the walls shrink and the cage speeds up.
• Chained cage: the cage is dragged toward heart markers. The second version adds a grid of spades. Match the pull, and arc around a spade instead of riding the chain through it.

The screenshot shows the spade wave inside the green box. TheConstructer's changelog also describes a chain sound on the red-heart attack, a grappling-hook wave on Hardmode, and an orange attack added in that mode.