There is a slight bug with the spikes.
When you jump without being in the range of the spikes and then you pass over the spikes come out even if you do not touch the ground. I think that if you jump without touching the spikes and then you go over they would not have to leave since you do not make any movement touching them.
I think the correct thing would be to do the same thing with the spear as you pass over them jumping that they did not come out and kill you.
Customer support service by UserEcho