My goals where to create a new game Entity that gives the Player (or an different Actor) special powers or features by injecting a new State.
First scheduled power-ups are related to Eating and Bombs:
I saw an interesting video on YouTube about the history of Quake development.
I like the idea that id Software used for Quake I in order to cut some production costs and additional development headaches. Some weapons come in pairs of two, one basic and one upgraded: Shotgun - Double-Barelled Shotgun, Nailgun - Super Nailgun, Grenade launcher - Rocket launcher. Apparently event the Thunderbolt had an upgraded version but they scrapped it.
I'm still tinkering with the way weapons upgrade will work and look in-game.
Full video logs: