When you have more than 1 Queen and you are defending your nest with them, they do stack on top of the player and each other. Essentially hovering in the air over the floor. When the player and the queens move the effect gets multiplied. It’s like they are using a staircase. This gets as far as one or both queens can disappear in the top of the window.
See Screenshots
Edit: It does not matter which form the player has. (basic worm or any evolved form)