The map editor is in Foe mapping mode (also known as "Foemap mode").

Foe mapping allows you to specify where random battles can happen. Whenever the hero walks on a tile with a foe map number, the player has a chance of encountering a random battle. The number is the same as the Formation Set ID number from the Formation Set Editor. Only one formation set can be assigned to each tile.

{{mapedit_basic_controls}}

Press < and > to change the current formation set number, or type in a number or use the MOUSE WHEEL.

At the top right corner the current drawing tool is shown. Press SPACE or LEFT CLICK to draw on the foemap. The tools are:

D - Draw tool:
  Press SPACE/CLICK to mark a tile
  with the current formation set
  number. You can hold down space and
  move the cursor, or drag the mouse
  to draw lines.

B - Box tool:
  Press SPACE/CLICK once to place one
  corner of the box, and SPACE/CLICK
  a second time at the opposite
  corner to draw a rectangle.

F - Fill (Paint bucket) tool:
  Flood fills a continuous region of 
  a single formation set under the 
  cursor with the current formation 
  set.

R - Replace tool:
  Replaces completely across the 
  whole map one formation set (that 
  of the tile under the cursor) with 
  the current one.

P - Paint on Layer # tool:
  Finds the continuous area on the
  current tilemap layer under the
  cursor, and sets the formation set
  for all those tiles; like a flood
  fill of a map layer except that the
  map layer isn't modified. You can
  use PageDown and PageUp to change
  the selected layer. For example,
  you can use this to 'paint' a
  forest path with an encounter
  formation.

M - Mark tool:
  Use to select a rectangular of the
  map to copy. Press SPACE/CLICK once
  to place one corner of the
  rectangle, and SPACE/CLICK a second
  time at the opposite corner. The
  tool will then be changed to the
  Clone tool. Mark copies the visible
  tilemap layers, wallmap, foemap,
  and zones in the rectangle.

C - Clone tool:
  Press SPACE/CLICK to paste a
  selection copied with the Mark
  tool.  You can switch to different
  editing modes to preview the
  changes to walls, foemap, and
  zones.  If default passability is
  on (press CTRL+D to toggle), the
  wallmap will updated using default
  walls instead of the copied walls.
  Only visible map layers are
  modified (press ALT+~ to toggle
  visibility of the current map
  layer), so a map layer has to be
  visible both when Marking and when
  Cloning.

Also,

CTRL+W paints the tiles visible in the window/screen with the currently selected formation set number.

CTRL+Z undoes a change to the tilemap, wallmap, foemap or zonemap. Changes to NPCs and doors are not undoable. The undo history buffer is near-infinite, but certain things cause it to be cleared: resizing the map, deleting or swapping map layers, erasing map data, and leaving the map editor.

CTRL+Y redoes an undone change.

CTRL+S immediately saves, useful when live-previewing a game.

To remove random battles from a tile, press DELETE (or change the formation set number to 0).

Press G to set the selected formation set to the one under the cursor (eyedropper tool).

TAB toggles a blue rectangle that shows roughly what area of the map you are currently looking at.

~ shows a minimap of the entire map.

CTRL+N toggles whethers NPCs are visible.