Behold and be Amazed! I used neither of those two things ('cause I'm an idiot) and used the most caveman solution I could think of. Every tick the character's head rapidly spawns particles that travel down at a slow yet constant rate. If the particle gets too far from the head, it gets deleted. If you spawn small particles in front of the character, and larger particles behind the character then the illusion is complete! If you want to make the illusion more convincing, you can have the game draw particles between particles so that the illusion doesn't break at high speeds. You can even add effects for wind by changing the direction the particles slowly move in.