# War Caster > [!info] Feat Details > | | | > |---|---| > | **Source** | Player's Handbook (2014) | > | **Categories** | Combat, Warding | > | **Prerequisite** | The ability to cast at least one spell | --- ## Description You have practiced casting spells in the midst of combat, learning techniques that grant you the following benefits: - You have advantage on Constitution saving throws that you make to maintain your concentration on a spell when you take damage. - You can perform the somatic components of spells even when you have weapons or a shield in one or both hands. - When a hostile creature's movement provokes an opportunity attack from you, you can use your reaction to cast a spell at the creature, rather than making an opportunity attack. The spell must have a casting time of 1 action and must target only that creature.