The encounter begins with the Mindflayer and its two Human Thralls concealed behind the central spire.

When someone moves within range of the central spire, the first Human Thrall steps out and watches the players. If questioned, it answers in simple monosyllables where possible.

When several players approach the water's edge, the second Human Thrall crosses the water westward, then slowly moves along the wall of the cavern attempting to encircle the players, staying within 10 squares of the Mindflayer as long as possible.

When combat is engaged, the second Human Thrall repeatedly attacks the nearest opponent with its club. The first Human Thrall may move to engage the players, but always remains within the Mindflayer's move radius. After one or two rounds, the Mindflayer moves to a square adjacent to the first Human Thrall and makes its Tentacles attack against a likely enemy.

While grabbing an enemy with its Tentacles attack, the Mindflayer will always use its Bore into Brain attack on that enemy. The first Human Thrall will always attempt to manouvre to a potition adjacent to the Mindflayer, in order for it to use the Interpose Thrall ability. When the first Human Thrall is near death, the second Human Thrall makes its way to the Mindflayer as quickly as possible, for the same reason.

None of the three will retreat from combat (except the Mindflayer, when bloodied, using its Bloody Retreat ability; the Human Thrall will move to follow, and the pair will regroup, attempting to draw the combat to a setting of their choosing.)

When faced with several strong enemies, the Mindflayer will use its Mind Blast attack to daze as many as possible. If it still has its Action Point, it may then spend it to attack one of the dazed enemies with its Tentacles.