[konidias]

You should make everything that is important (like saving data or calculating data) serverside. Stuff that should be made clientside is stuff such as lights, which would be the same if they were shown serverside or clientside anyway.

Think about it. If each client is seeing a light clientside, then they are all seeing the light, so it doesn't need to be serverside. Serverside scripting also prevents hackers from easily changing data... Lights are mostly just for show and stuff, so it really doesn't matter what hackers would do to them clientside.

Basically:

Important things that need hack-prevention - serverside
Everything else - clientside

There are a few exceptions... like if you have an npc that moves through levels, then it needs to be serverside, because it's x/y coordinates need to be more global and not tied down to each client.