The 'Custom Space Marine Chapters' meme celebrates and satirizes the Warhammer 40,000 hobbyist tradition of creating 'homebrew' armies. While the game provides established factions like the Ultramarines, players often invent their own chapters with unique color palettes and backstories. The meme format usually highlights the contrast between a player's often flamboyant or neon-colored miniatures and the intensely dark, tragic lore they write for them. Since the rise of communities like r/Grimdank, these memes have become a way for fans to poke fun at the 'Mary Sue' tropes often found in custom lore or the struggle of choosing a paint scheme that doesn't look like a bowl of fruit salad.