I'm making a mob follow a player, on their left in 1.9. So, whichever direction they look, the mob will be teleported to stay on their left. Here are the commands I have to teleport to the player.
Repeated block, then chain block.
/tp @e[type=ArmorStand] @p /tp @e[type=ArmorStand] ~1 ~-.5 ~ ~90 ~
What do I need to do to teleport the mob to the left side of the screen always?