public String moveCardOntoCardFromDeck(int boardIndexTo) {
        if (boardIndexTo == 0) {
            //Moving onto dragon's tail, anything goes.
            board.get(0).add(deck.poll());
            return "";
        } else {
            String result = moveCardOntoCard(Arrays.asList(deck.peek()), boardIndexTo, 0);
            if (result.isEmpty()) {
                deck.poll();
            }
            return result;
        }
    }