Placeables
There's 2 very different kind of placeables:
Static
Non-Static
While it is a simple “checkbox” in the placeable properties, it changes a lot of things.
Non-Static Placeables
They can be targeted by players
They can be animated / have visual effects
They can be moved
They are only seen by players when their character gets in a perception range of the placeable
Since that are loaded by players dynamically, many non-static placeable can make walking around an area laggy for players. Areas shouln't have more than 100-200 non-static placeables.
Static Placeables
They are loaded by players when loading the area
They can't be targetted, be animated or have visual effects, moving them wont by perceived by players until they re-enter the area
They don't really impact players performance so you can add almost as many as you want to your areas (but ideally less than 1k)
Adding Visual Effects
To add Visual Effects to a placeable object, set it to non-static (dynamic), set the placeable OnHeartbeat script to “plcvfx_self” and add integer var PLCVFX_SELF, (or PLCVFX_SELF1, PLCVFX_SELF2, PLCVFX_SELF3, etc) with the desired VFX index number(s).