How to best replicate Tweenservice to Server

In a ability I’m currently making I’m handling all of the visuals with the exception of cloning & positioning the model on the client side using :FireAllClients, however what I intend to use as the hitbox is a part of the model and grows with the rest of the model using Tweenservice over the course of a second.

So my question is, how do I make the server also see the model growing so I can do the hit detection in the way I want to.

Not too good at describing it, hope I can get some help from this though.

do the same thing in the server, change the size of the hitbox using tweenservice or other methods.

I don’t get what you mean exactly but in general there’s no need to replicate the effect on the server, instead just set the size (on the server) of the hitbox after the tween ends. Though if you really want it to gradually get bigger on the server as well then there’s no point in tweening on the client because it would get cancelled anyways if you try to manipulate the size on the server while the tween is playing.