Bosses are where Eternal Palace Sakura's design is most explicit, and where a wiki earns its keep fastest. The publisher's own words: the game has "frenetic boss fights", and bosses demand pattern-learning and dodge timing. Those two phrases together describe a fight where the answer to everything is the same: watch, then move.
Frenetic is the word to take seriously. It rules out the slow, readable bosses of the classic action-RPG tradition, where a big attack gives you half a second of free time. In a frenetic boss, the safe rhythm is: learn the pattern, dodge through the flurry, punish the recovery. The punish window is short. That is the skill test the game is built around.
This is the decision that decides whether a run succeeds. Evasion is safer: if you learn the pattern, you take almost no damage and you can keep the run alive indefinitely. Charge-up is faster: if you can land the commit, you can end a long fight in a moment. Against a boss whose recovery window is tight, the two swap places — a charge-up that lands is worth several evasion cycles, and a charge-up that gets interrupted is worse than doing nothing.
The official copy promises "exciting endgame content" and tells you to "increase your powers and take on exciting endgame content" — which is the publisher telling you the endgame is gated behind the powers you have built. With fifty-plus fighting arts and permanent cross-run progression, the endgame is where a long-term build finally pays off, and it is the reason a wiki is worth keeping around.
Individual boss names and their move lists were not publicly documented at the time of writing, so they are not listed here. The demo is the fastest route to meeting the first one, and if you write down what you see, the rest of the wiki can be built from player reports like yours.