Today's something of an historic occasion; Zynga has released its first game on Steam. Solstice Arena is a free-to-play MOBA also available for iDevice, developed by A Bit Lucky, which Zynga acquired last year. It was nominated for a Unity Award for Best Gameplay and Community Choice this year. A Zynga game! On Steam! Madness, chaos, cats lying down with dogs, et cetera.