Have you read "Alice's Adventures in Wonderland" and its sequel, "Through the looking-glass and what Alice found There", by Lewis Carroll? I assume you may have inspired in these classic works regarding your particular game named Prison. As a matter of fact, Alice Chess is named according to Alice's adventures in "Through the looking-glass ...", a chess variant invented by Vernon Rylands Parton. It is the only chess variant played on two boards with the usual 32-piece set, so there are two subvariants: Alice Chess I, all pieces start on board A, board B starts bare; and Alice Chess II, white pieces start on board A while black ones start on board B. The standard chess position is used but it is likewise possible to use any of the 960 starting positions of Chess960, thus generating 2,800 and more ways to start a game, whether on one or two boards. The site offering these variants and those mentioned by you is http://www.Scheming.Mind.com/ 

Also on each move, a player must pick up a card to replace the one they played.

I almost forgot about another game I made up earlier called Prison. It takes place on a four-by-four grid, with two kings (one red, one black) in opposite corners. The black king moves first (just to mix things up a little.) Kings can move one space forward, backward, or to the sides, but never diagonally. The game also uses a standard deck of 52 cards.

Both players start out with five cards in their hand. On each move, a player must move his/her king AND play a card on any of the four adjacent squares (again, not diagonal.) A card may not be played on a space that a king occupies or already has two cards on it. If a player cannot do both of these requirements, then that player loses.

The black king can only travel on spaces that are marked black or neutral, and never on spaces that are marked red or blocked. The red king can travel on spaces marked red or neutral, and not on those marked black or blocked.

The two kings may not occupy the same space.

On a turn, a player may move first OR play a card first, as long as the next step fulfills the other requirement.

The way the cards work:

The first card to be laid down on a space determines that space's mark. A red card marks a space as red, and a black card marks a space as black.

After that, a second card may be played on that same space if need be.

A black card placed on a space that is already marked black makes that space permanently black.

A black card placed on a space that is already marked red AND the black card is of higher value than the red card transforms that space into a permanently black space.

A black card placed on a red space where the black card and the red card have equal value makes that space permanently neutral.

A black card placed on a red space where the black card has a lower value than the red card marks that space as permanently blocked. Neither king can travel there again.

Similar rules apply for playing a red card.

The black player may play red cards if needed, and the red player may play black cards if needed.