With Dragon Age 4 in development, fans have had a lot of time to think over Solas' plan. In Trespasser, he could reveal a lot to the player, such as his plans to tear down the Veil and his spies within the Inquisition. It is also likely that he only divulged a tiny part of his plan, as he does frame himself to possibly be the main villain coming into Dragon Age 4.
Tearing down the Veil is a lot to comprehend. It will change Thedas in many ways, and there are secrets locked behind the Veil just waiting to be discovered. Once all is considered, a torn-down Veil is just the tipping point of much bigger issues for Thedas. While the Veil getting torn down by Solas is bad, what will happen after will likely be much worse and more complex.
Dragon Age's Biggest Ethical Question Is One-Sided
In Trespasser, Solas mentions that tearing down the Veil will require him to sacrifice the current world to save the old one. In discussions by fans, a lot of theories believe magic will come to all people in Thedas, or perhaps just the elves — who will also regain their immortality. According to Solas, the Evanuris are sealed beyond the Veil as well, so they will be free.
As for the demons and spirits that live in the Fade, it is unknown what will happen. Demons have thirsted to cross over, and with the Veil torn they finally could appear in the physical world without possessing people. There could also be a lot of spirits that end up like Cole, and the Old Gods are believed to be in the Fade as well. Some theories believe the Old Gods and the Evanuris are one-in-the-same, but there is the possibility that these Old Gods truly are powerful dragons.
Whatever the case, Solas lays out that tearing down the Veil will destroy the world, but he does
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