What you want to ask is why the Food Wars Mouse gem icon becomes dark? Weapon levels don't match. Displayed according to query Jiuyou.com. The gems obtained in the game are used to be embedded in the main and secondary weapons. If the weapon level and the gem level do not match, the gem embedding will fail and the icon will darken. On the contrary, the gem icon will light up after the embedding is successful. "Food vs. Mouse" is a highly strategic casual game and a puzzle strategy tower defense game.