Legendary Pokémon in Red, Green, Blue & Yellow
Articuno, Zapdos, Moltres, Mewtwo, and Mew notes across Gen I.
Articuno, Zapdos, Moltres, and Mewtwo are the standard legendary encounters. Mew remains event-only for normal gameplay planning.
Location
Seafoam Islands
When Available
Available once you can reach and navigate Seafoam Islands with Surf and Strength.
Capture Tips
Save before the encounter, bring status moves, and stock Ultra Balls.
Location
Power Plant
When Available
Available after Surf opens access to the Power Plant area.
Capture Tips
Save first, avoid knocking it out, and use paralysis or sleep if your team can apply it safely.
Location
Victory Road
When Available
Available late in the main story while traveling through Victory Road.
Capture Tips
Prepare before entering Victory Road, save before battle, and bring enough high-grade Balls.
Location
Cerulean Cave
When Available
Available after becoming Champion.
Capture Tips
One of the strongest encounters in Red and Blue. Save before battle and use status support.
Location
Event distribution
When Available
Not normally obtainable in standard Pokémon Red and Blue gameplay.
Capture Tips
Treat Mew as event-only for normal guide and Pokédex planning.
Note
Glitches are not considered normal intended gameplay in this guide.
More Gen I Guide Sections
Shared Walkthrough
Follow Kanto from Pallet Town to Champion with version notes.
Version Differences
Compare release history, starters, encounters, and presentation.
Exclusive Pokémon
Check version availability and trade-planning targets.
Pokémon Green Differences
Understand Japan-only Green without confusing it with Blue.
Yellow Differences
Pikachu starter, gift starters, encounter, and trainer changes.
Gym Leaders
Badge order, type specialties, key Pokémon, and counters.
TM & HM Locations
Find Cut, Fly, Surf, Strength, Flash, and key battle TMs.
Elite Four
Prepare for Lorelei, Bruno, Agatha, Lance, and Champion.
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