Tension is an important mechanic in Xenoblade Chronicles X. Tension is quantified by Tension Points, or TP, with an initial maximum amount of 3000 TP. They are earned and accumulated by performing Auto-Attacks on enemies during battles. Mediators can also earn them from using Arts. This game mechanic is somewhat comparable to the Party Gauge mechanic in Xenoblade Chronicles.
Tension Points can be used to reanimate an ally. After progressing through Chapter 5 in the story, an Overdrive can be activated when 3000 TP have been accumulated in the Tension Gauge, consuming 3000 TP. In addition, some arts have "TP" on their palette icon, indicating that the art consumes 1000 TP per use.