Metroid 2 (Gameboy)

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Bad Ending - Samus running in place

Completion time of 5+ hours.

Codes

These are game genie codes

unlimited energy 00F-36B-E6E
unlimited missiles 80F-6DD-7F6

Different Ending

Beat the game in under three hours, and when Samus shows up in the ending, you'll see her in a bikini.

Good Ending - Suitless Samus

Completion time of less than 3 hours.

Stalljump

If you do a directly vertical spinning jump and hold up, Samus stalls in midair. Perfect to use with the screw attack, since most if not all attacks will do absolutely nothing to you during it.

Standard Ending - Samus stands still

Completion time of 3-5 hours.