Grimoire is basically the same thing as prestige in Call of Duty. You don't have to be good to get high Grimoire, you just have to put time into it. But, higher Grimoire players typically are more reliable. You run into a high Grimoire player that doesn't seem to have eyeballs and thumbs once in a while, but most are good to have on your team. Medal score is almost the same as Grimoire. Typically the more you have, the better you are. I myself only have 1.5 Million, yesterday evening I absolutely took a violent dump on this team in Trials, I got some hate mail so I decided to look up the K/D's. They all had 3+ million medal score and each of them had between a 1.0 and 1.2. My cousin is an absolute monster at this game. He has like 4300 Grimoire score and only has 500k medal score but he would probably destroy your dreams when you look at his Trials K/D. AwesomeSniper82.