[x] All units are always visible
[x] Tiles can be impassible, walls or walkable
[ ] Tiles may cost extra movement to pass
+[ ] Every map map may have up to 8 named npcs (saved as killed flag in sram based on map-id)
+[ ] Every map may have 4 containers containing up to 4 itmes each. (collected flag saved in sram based on map-id)
+[ ] Every map can call a custom load routine and save routine based on map-id (look up from a table)
+[ ] Every map gets 8 bytes of save data
## Units