Join MySQL Lookup tables
So I finally got this to work by using the following query:

SELECT
    games.*,
    games.game_id game_u_id,
    GROUP_CONCAT(DISTINCT genres.genre_name) genre_names,
    GROUP_CONCAT(DISTINCT themes.theme_name) theme_names
FROM
    retro_games games
LEFT JOIN retro_game_genres all_genres ON games.game_id=all_genres.game_id
LEFT JOIN retro_game_themes all_themes ON games.game_id=all_themes.game_id
LEFT JOIN retro_genres genres ON all_genres.genre_id=genres.genre_id
LEFT JOIN retro_themes themes ON all_themes.theme_id=themes.theme_id
    WHERE games.game_id='1375'
GROUP BY games.game_id


Wondering if this is the most efficient way of doing it though, or is there another method that would faster? It's fine for my one row of 1375 but it will be eventually used on thousands of rows when they view all games.