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.
Got it! Someone has finally recreated Doom 2 in the Diablo 2 engine. For those who still get motion sickness from Doomguy's blistering sprint, here's a fairly awkward solution: play Doom 2 as an isometric ARPG ala Diablo 2! Someone has made a tentative effort to make such a thing happen, and the video above shows how it looks. It's the work of YouTuber DolloM, who has dubbed the mash-up Doomiablo.