A Grand Game (Find two words)

Question

Find 2 relevant (but not strictly related) words using a logical method. One ends in 'R', the other in 'E'.

The method should be one which leads to the exact and specific letters for each word (no extra letters, but anagrams required).

Here is a clue to guide you:

The ruler may gaze at the sea, for it belongs to no man. From tea, however, he must abstain, for it belongs to night.

Text version:

O   C   D   F   S   J   O   L
A   G   S   N   M   E   V   C
X   U   Q   Y   Z   T   L   D
I   C   A   B   Z   E   Y   I
T   E   P   X   K   V   W   M
I   H   L   I   R   N   P   A
J   F   R   G   D   C   M   F
(row of whitespace)

Hint:

For the first step, focus on the bottom right quadrant and use a combination of the strategies of @humn and @bass.

Hint 2:

Trying to back-solve from the number of words or last letter will do more harm than good. To begin, focus solely on the grid and name of the game. Almost every letter has been placed with care.

Hint 3:

Start small and work up. Consider shape and orientation.

Hint 4:

The castle may not watch the bee, or it would cease to be a castle, and instead be a small river.

Answer 1

The two words are

MASTER and SACRIFICE

We can start by noting that

There are several spots, where a chess piece can find its name in the squares which it can reach:

Here we have in order: pawn, rook, bishop, knight, king.

The queen is a bit more problematic because there are four possible squares:
However, a closer inspection reveals that, in addition to the letters of their respective names, the first five pieces only threaten squares with letters which do not belong to any of the pieces, i.e., letters CDFJLMQVXYZ. The only possible position for the queen is then the square with T.

Then, the starting positions anagram to MASTER.

If we colour each square that is reachable by those pieces, we get this:
The remaining letters spell out SACRIFICE.

The title probably also hints at these two words (grandmaster and game as in prey, perhaps?). The clue gives a hint about the constraint on the threatened squares. The king can threaten the square with a c since none of the pieces has c in them, but it cannot threaten a t since it is in the word knight.

Answer 2

I had to use all the clues, and the result is still less than overwhelmingly clear, but here's what I've got:

Starting from the title, we are very likely talking about a game.

Looking at the grid, we have an 8x8 board. So chess or checkers, maybe?

An obvious word related to all games and ending in "R" is

"player"

A word that goes ending in an "E" that goes well with everything above (except the 8x8 part) is

"single".

So, in order to fit the board size in I googled

single player chess

and indeed I could use the rules of that game to find those two words on the grid:

Consecutive letters are separated by chess piece capturing moves, as you'd find in a game of SINGLE PLAYER chess.

I had to re-use the letter L though.

Answer 3

One of the words might be . . .

E L I X I R

Method of finding:

I went retrograde and diagonal, as usual, working backward from R

. . . although I don’t get how that relates to “grand”.

This might deserve an ^vote but not a checkmark.