Microglia

Microglia are the resident immune cells of the brain and spinal cord. In Arborwake, the player's Ranger is a microglial cell, and so are all three possible companions.

In the brain#

The points below summarise the project's research reviews. They are simplified and hedged.

• Constant sampling. Healthy microglia move their fine processes all the time to sample their surroundings, even when nothing is wrong.
• Local territories. Microglia are spread through the tissue, each covering a local area.
• Processes are not the whole cell. A process can reach quickly while the cell body stays put. Moving the whole cell is slower and different.
• Arousal is not inflammation. In mice, being awake rather than anaesthetised changed microglial process behaviour, partly through noradrenaline signalling. A changed shape alone does not prove an inflammatory response.
• Many readouts. Shape, movement, gene activity, engulfment (phagocytosis) and cytokine release are different measures. One changing does not mean all do.
• Not the same as blood macrophages. Microglia differ from border-associated macrophages and from monocytes that arrive from the blood.
• Helpful and costly. In some stress models microglia seem protective (for example through BDNF); in others their signalling is part of a costly relay. Context decides.

In the game#

• Bodies: cute, slime-like and recognisably cellular, never humanoid. Ordinary movement has no visible ropes; action tendrils appear only when a cell works.
• Verbs: Tend removes a real source, Care supports a target, and processes reach before the body follows.
• Roles: the companion roles observer (Mote), roamer (Fen) and keeper (Pip) are fictional work preferences. The dossier is explicit that they are not biological subtypes.
• Classes: Sentinel, Warden and Coordinator are "styles of helping", not cell phenotypes.
• No M1/M2 factions. The plan forbids good-versus-evil microglia and "evil activated microglia".

Development#

• The named cast (Fen, Mote, Pip, Rill, Cress) were accepted on 2 November and animated with idle, start, move, stop and tend. They are larger than the Ranger, and that is accepted.
• The Ranger and the generic Pip and Mote keep their original size and colours (user, 2 November).
• In the alpha Microglia are the player character and the main residents in the Placeholder alpha.

See also#

• Ranger
• Science guardrails
• Stress-associated neuroinflammation

Sources#

1. .GAME_PLAN/ARBORWAKE_COMPANIONS_NARRATIVE_AND_SYSTEMS_DOSSIER_v0.5.md (working copy, not in Git)
2. .GAME_PLAN/ARBORWAKE_STRESS_NEUROIMMUNE_RESEARCH_REVIEW_2026-10-29.md (working copy, not in Git)
3. .GAME_PLAN/ARBORWAKE_THE_LONG_WAKE_COMPLETE_GAME_PLAN_v0.5.md (working copy, not in Git)
4. 16c9aab43:art/characters/named-cast/anim/README.mdcopy