Day 20: Phendrana Drifts (Metroid Prime)
Metroid Prime was the modern reimagining of the classic Metroid series as a first-person shooter. Well, I say "modern", but the game is over a decade old at this point. Ice is important to the Metroid series, as it is the weakness of the Metroids.
After getting through the fiery Magmoor Caverns, Samus arrives in this snowy area. There's lots of snow and ice, and some frosty Chozo ruins around. Like most places Samus visits, the local wildlife is hostile to her.
That's a Baby Sheegoth up there. Its hard shell deflects frontal attacks, but it's vulnerable from behind. The adult version shows up as a midboss later on. There are also Crystallites, which look very similar to Bergmites.
Surprisingly, Samus doesn't find the Ice Beam here; instead, after facing off against the adult Sheegoth, she gets the electric-based Wave Beam. This is quite handy for attacking robotic or energy-based enemies, and homes in on enemies too. After getting that, she heads further into the icy ruins, and discovers a Space Pirate base in the area. Storming the base grants Samus the Thermal Visor, which allows her to track heat signatures. This doesn't seem like it'd be useful in a cold area, but it actually comes in quite handy, particularly since the lights go out as soon as she picks it up.
Once she escapes the darkened Pirate base, she can head to the boss, a rock monster named Thardus.
To defeat it, you first have to search for its Phazon-infused core with the Thermal Visor, then shoot at it to reveal it to the standard visor.
Later in the game, you come back here and venture into the depths of Phendrana to find the Gravity Suit, an upgrade for Samus' armor that allows free movement in water. Still later, you can come back after you've picked up the heat-based Plasma Beam to melt the ice and claim a lot of hidden pickups.
The music for the area is quite soothing, while the Phendrana Depths has a more intense version.