HTR, Hostile Tally Rank is a score from 1 to 20 in The Epic Space Game. Every mimic kill achieved raises your score.
Your HTR Score will directly affect your speed, turnrate, and rate of fire of any ship you pilot. It will also affect fuel consumption.
It's a good idea to raise your HTR score in a Artemis before piloting a Cargoship. You'll be able to travel faster and evade fire more easily.