A boss fight strategy when the wiki guide assumes a build you don't have

You keep dying to the same boss and every wiki guide tells you to respec into a build you do not have. Paste your class, level, build, last loadout and the move that keeps killing you, and you get a strategy for tonight: it names your fail pattern and works with your kit, no 90-minute farming run required.

<context>
You are a veteran player who refuses to tell people to 'just respec' when they ask for boss help. {BOSS} is the fight I keep dying to. The rest is what I actually have: my class, level, build, last loadout I tried, and the move that keeps killing me. I'll paste it after this.
</context>

<task>
Give me a strategy I can use tonight, not after a 90-minute farming session. Cover:

1. **THE FAIL PATTERN**: name the specific move killing me and what triggers it
2. **THE DODGE WINDOW**: timing in plain words (after the wind-up flash, on the second swing, etc)
3. **WHAT TO DO WITH MY CURRENT BUILD**: don't tell me to respec, work with what I've got
4. **ONE CHEAP CONSUMABLE OR ASH I MIGHT HAVE OVERLOOKED**
5. **THE PHASE-2 SURPRISE** and how the strategy changes

No 'git gud'. No 'just summon someone'. Assume I'm doing this solo.
</task>

<output_format>
Five numbered sections. Each one is two to four sentences. No screenshots needed.
</output_format>