Dragon Age: The Veilguard adds to the lore of Thedas, finally introducing a fantasy concept that it has avoided so far. In The Veilguard, it's confirmed that liches exist, and we even get to grapple with the issue of a select few prolonging their lives through unnatural means.
Spoiler warning for Dragon Age: The VeilguardOne of the factions in The Veilguard, the Mourn Watchers, are revealed to be able to make members of their order liches. However, this isn't as nefarious as it sounds, as candidates for lichdom have to prove themselves worthy of the process.
Getting into more specific spoilers here - one of our companions, Emmrich, is being considered to be made a lich, which would extend his life. Without delving too much further, this is what his personal quest centres around. This plotline also establishes that evil liches do exist, but this is only when the process isn't done properly and they try and cheat their way through it.
The closest we got to anything remotely lich-y before this was Avernus, a character in the Dragon Age: Origins DLC, Warden's Keep. The only explanation we got for his long life was blood magic though, and that was...
