, Pay 1 life, Sacrifice this land: Search your library for a Plains or Island card, put it onto the battlefield, then shuffle.
Flooded Strand is premium fixing — one of the ten Onslaught/Khans "fetch lands" that quietly do enormous work in any Azorius (or blue/white-touching) deck.
The value goes far beyond mana. Fetching thins your deck and lets you grab any land with the Plains or Island type — that includes dual lands like Tundra, Hallowed Fountain, and Glacial Fortress, so a single Flooded Strand can find multiple colors. That flexibility is why it's auto-include in two- to five-color manabases.
It also enables synergies: shuffle effects (Brainstorm, Scroll Rack), landfall triggers, and graveyard/delirium strategies. The "pay 1 life" is trivially cheap in EDH's 40-life format.
Play it in any deck with white or blue and a reasonable budget. The only reasons to skip: tight budgets (fetches are expensive), mono-color decks running basics where thinning is negligible, or landfall decks that prefer untapped lands hitting all at once. Otherwise, fetches are about as close to default includes as lands get.