Yifan Yin

Skeletons also do the same, it follows the chance of people being left or right handed

Evokers (or maybe illusioners) perform their attack even when their target isn't in their sight and also when they taking any damage from player. The vexes it summons will search for targets itself

To make the link with villagers

The end city structures are mean't to be challenging(the parkour part), the slab placed directly above another is to purposely make the climbing more difficult.