So I wanted to add a filter every time I kill an enemy for a short period of time, and vice versa. Kinda like GTA V style.
Make filter asset. No physics, scale it up, set right opacity. Add delay node (0.1s or something like that) and remove node. Then spawn it, when desired action is triggered.
I know this might sound a bit stupid but where might you find a filter asset, I'm pretty new still yet
You make it. If it is 3D game, import cube from assets library. If it's 2D game, import rectangle.. Set it's color to red or blue or what filter color you like. Change opacity, so you can see through it, and creates filter effect. In 3D model / Animation node, change scale to 50 or something, so it covers whole screen. And into that asset, add delay node (0.1 seconds should be okay), and connect remove node with delay node. In actor's or enemy node map, use spawn node, to spawn filter asset. Probably need to connect spawn node with if collide node or defeat node.
If you open asset's color option (to set its color), if you're using PC, then you can see "Alpha channel" field. Lower its value to reduce its opacity. In mac, it is named as "Opacity".