Conversation so far:
What legacy did Lapu-Lapu leave behind?
Lapu-Lapu is regarded, retroactively, as the first Filipino hero.
Why was Lapu-Lapu regarded as the first Filipino hero?
Lapu-Lapu was the first native to resist Imperial Spanish colonization/colonization.

Question: How did this legend begin?
Self-contained rewrite: How did Lapu-Lapu's legend begin?