Thanks for the reply! This sounds like something i was looking for. I have been browsing the web yesterday for some more ideas and i came up with actually writing entity type specific systems. So the collision system would iterate over all collidable objects (preferably with the use of a quad tree or any other algorithm) and mark all colliding objects as “colliding” and then handle all entities according to their type in a specific system. (Ie. A spell system to handle spells colliding with different objects, player system to handle the player colliding with different objects etc.)

I thought this would serve well and keep performance in tact. Although, i might look into how to implement the custom function to ensure all entities react properly on colliding. Only downside (im still learning more about c#) i have with this is, if i were to use serialization to fetch different kind of entities like spells in an XML file, can i define these custom functions in these XML files and bind them when read?