Haven't played Portal yet. At the moment, my favorite is still the ending of Skies of Arcadia. As the music plays, a changing page gives you the fates of all of the other characters you've interacted with through the game (and gives, I think, a potential plot hook for a sequel - at the end, Hans becomes chief engineer of the rebuilt Valuan fleet, and Pinta also winds up working there - with the avowed intention of one day exploring the Moons. Maybe someone lives there - and maybe they're a little resentful of having had their worlds torn apart during the Rains of Destruction, and again when the renegade Valuan admiral tried to take over the world using the power of Zelos...).
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.