This is one of many possible schemes for the AI of an enemy NPC in a first-person shooter game. As written, it should (disclaimer: have not coded it yet) be fairly straightforward to translate it to a UE4 blackboard, behavior tree, and tasks, services, and decorators.
A first-person shooter (like Robot Dynamite) needs a first-person character. In contrast to a full third-person humanoid character, all the player can see is the gun and the first-person arms mesh. However, if it is a multiplayer game, or even a single player game in which one can look in a mirror or a closed-circuit video, the full third-person mesh is visible.
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