Hi!
Thanks for the question: The Tornado uses particles, which work heavily on FPS. Depending on the hardware of the end-user they can handle a certain amount of particles at the same time. This is why we chose to spawn a tornado for each client individually. It is possible to synchronize one or two tornados with the risk of the end-user experiencing loads of FPS drops during these disasters if they were spawned near each other. So, yeah. 1 tornado for each client was what we chose for. It spawns near them at a random point in a 100m radius, then moves around randomly.
0.03/0.04ms active (tornado).