Opportunity attacks
Moving away from an adjacent enemy without disengaging carefully provokes a free attack from them, punishing careless repositioning and making retreat a tactical decision rather than a free action. Baldur's Gate 3 and Divinity: Original Sin 2, both drawing from tabletop D&D rules, use opportunity attacks to make melee engagement sticky — once you're in someone's threat range, leaving costs something. Designers use this to prevent hit-and-run kiting from being universally optimal, to make positioning commitments meaningful (engaging melee is a real choice with a real cost to undo), and to give reach and control abilities (that punish or prevent movement) tactical value. Key decisions: what triggers it (any movement away versus only fully disengaging), whether abilities exist to avoid it (disengage actions, mobility spells), damage severity relative to the risk of staying engaged, and clear UI so players know which enemies threaten them before moving. Pitfall: opportunity attacks the player can't see coming (unclear threat ranges) feel like a trap rather than a fair tactical rule — visualization of threatened tiles is essential.
- Dev effort: Small
- Timing: Turn-based
- Common in: crpg, tactics