While Valve's game output isn't as big as it was in the mid-2000s, the Washington-based developer has plenty of IPs that are beloved to this day. One of these is the seminal first-person puzzle game Portal, with the puzzles and witty writing still holding up. Fans have maintained interest in the franchise through mods and fanmade creations, ranging from complete overhauls of Portal 2 to a demake that makes it look like it was built for the Nintendo 64.