At the head of the planarian there is a brain under the eyespots. From the brain, there are two nerve cords, which connect at the tail. There are many transverse nerves connected to the nerve cords, which make it look like a ladder. With a ladder-like nerve system it is able to respond in a coordinated manner.
Adventure mode. From Diablo Wiki. Adventure Mode or AM is the primary end game type of game mode introduced into Diablo 3 in the Reaper of Souls expansion pack. Campaign Mode or Story Mode is the other primary game mode, where players must progress through the acts in order, complete quests, talk to NPCs, watch cut scenes, etc.
Dragon Blaze is an iPhone game with multiple game modes. Adventure mode is a story driven campaign that can be played on four difficulty levels. New players will start on Normal then advance to Hero and when they feel up for a challenge they are invited to try the game on Legend or Myth. Companions are unlocked when playing Adventure mode. Boss raids are Dragon Blaze PvE activities where four players join forces against an extremely powerful AI mob.