Resting his rifle on the window, Richard picks a target to aim at. This looked bad, he knew that, but he didn't fancy the outcome to surrendering to a group like this, particularly now they've already lost people, much better to the outcome of fighting. Besides, they had the defensive position here and they weren't that bad at fighting. They could manage.

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Taking aim at someone in the advancing group, preferably someone closer to Richard's position and who isn't next to the grenade.

Richard is Overconfident, so he's preferring to back himself over listening to the doubts.