Here comes some more easy to answer questions that don't really need their own thread.
1) While creating a multiplayer game, I know I can use xna for part of it. But for usernames and information like that, would I need to use SQL and set up a server to host games?
2) Imagine you're looking at stairs from the side:
In order to make my player move up the stairs without jumping, would I need to implement octrees into my cube creation?
3)Will HLSL be able to handle effects like creating a beam of light shining onto a player's position from a dark sky, or sparks like the wisps in Warcraft 3?
4)My AI in my game will be simple, much like League of Legends. You will be able to set a spawn point and with a click of a button you can send your troops to attack an enemy wall or tower. If your troops come into range of any other troops or the enemy's structures, they attack. What kind of AI scripting would I need for something simple like this?
Thanks again in advance