All Soulslike games can trace their roots back to FromSoftware's Demon's Souls, a game that combined the maze-like level design, and limited checkpoints of the Metroidvania genre with elements from 3D action titles like The Legend of Zelda: Ocarina of Time. The 2009 game also introduced online co-op and PvP invasions, long-standing systems that are staples of FromSoft games and the Soulslike genre to this day.