I got the power gamer label because I was explaining how I maximize the amount of XP units get in battle in Fire Emblem: Three Houses. You know...have your healer heal someone every round—even if it's just 1 HP—so they get experience, crowd your students around Byleth for her XP bonus, draw out the time it takes to kill enemy units that aren't doing much damage to your units, so that you can have multiple people gain XP from attacking or getting attacked, etc.
Does that make me a power gamer? 😁