There have been several tragic deaths throughout the Stargate franchise, but a select few were especially devastating to see play out on screen. The sci-fi franchise saw its characters risk their lives to protect the planet and their loved ones, and more often than not, they managed with only a few scrapes and bruises (and some instances of alien possession). However, on a few occasions in Stargate SG-1 and its spinoffs, the ongoing battle with the Goa'uld and other alien races meant the end of some beloved characters' time on screen.

https://screenrant.com/stargate-sg1-character-deaths-sad-ranked/