Player > Feats > Stand Still
You can stop foes that try to move past you.
When a foe provokes an attack of opportunity by leaving a square you threaten, you can attempt a melee attack as a reaction against that foe’s Kinetic Armor Class + 8. If you’re successful, the enemy cannot take any further movement for the rest of its turn. The enemy can still take the rest of its actions, but cannot leave that square.