SELECT
g.*, s.*
FROM
GAMES g
LEFT JOIN
(
SCORES s
INNER JOIN
(
SELECT
n.game_id, MAX(n.created_on) AS max_score_date
FROM
SCORES n
GROUP BY
n.game_id
)
y
ON y.game_id = s.game_id
AND y.max_score_date = s.created_on
)
ON s.game_id = g.id