Psionic Assault is an advanced micromanagement challenge. With a force of six high templar and eleven sentries, the player must stop a horde of zerg, protoss and terran attackers. The difficulty increases as reapers join the fray. The winner gets a bronze achievement for killing 75 enemies, silver for 150 and 225 for gold. Enemy units continue spawning after achieving 225 kills until 300 units are slain; no achievements are awarded for this, it is just a test of player skill.