Build a 1x2 building 2 walls high. Keep one end open to lure the mantis in and a door on the otherside to walk out of. Once in place the 2 walls behind it blocking it in and replace the doorframe with a wall. If it's agro on the walls fly straight up on a bird until the mantis is out of render distance then fly back down. . You should then be able to walk up to a wall without bugspray or gillie and feed it through the wall

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