I know this is an over used issue.
But truly can someone look through my game and find something that causes lag, I mean the game runs good at first, and doesn’t have too many things happening.
On some levels after a minute or two it will lag a lot, which changes the games difficulty a lot, making it nearly impossible to lose.
Here’s the game- https://flowlab.io/game/play/1116489
I’ve tried all the simple way of reducing lag (Des-pawning off screen object, stopping animations… etc.)
Try using the in-view trigger.
Using it on what?
I have it on everything that leaves the screen.
You may have a lot of proximity checks. Try asking a more knowledgeable person like JR_01.
I do have a ton of proximity checks, is there any way to make that lag less?
There’s an alternative to proximity checks, but I forgot what it is.
Raycast raycast raycast, one of the most important behaviors. If you don’t use em’ then you can say goodbye to any chances of making a recognizable game 
But how do I make a ray-cast that detects the area around it, just have like 20?
Only as much as you need, like 1 on each side. if you need 20 its a little worse, but still better than proximity
if you’d like to use proximity and delay lag or reduce it, use a parent object. Grazer has a blog about parent objects if you need help understanding it.