Dominion

Description
Dominion is an object placement puzzle where dominos must be placed to divide the grid into separate areas.

Rules
The challenge is to divide the grid into separate areas subject to the following rules:
 * 1) Each area has all copies of a single letter, but only that letter.
 * 2) Shaded dominoes divide the grid and can only touch at corners.
 * 3) Cells with letters are always unshaded.
 * 4) All regions must have at least one letter contained in it.

Example
A standard 10x10 dominion puzzle and its solution.



Variants
Unless otherwise indicated, standard dominion rules apply to all variants.

Triminion: Triominoes are used to divide the grid, however identical triominoes are not allowed to touch at the corners.