*hugs herself and giggles madly*
OXI. THIS. SO MUCH.
Totally with you, red lyrium specifically as lymphoma with a twist. Again, game-as-fade: our reality, our rules, bent but not broken. Blood cancer infecting the Stone: dwarves as lymphocytes, the ancient thaigs as lymph nodes, deep roads as bone marrow. Network of lyrium veins simultaneously functioning as the Stone's circulatory and nervous system.
Will try to explain thought process, but completely floored by flu at the moment so going to have to shove everything out of my head without much connective thought. Have faith you'll understand. Original disease reacts differently to races of Thedas than the Stone because they are fundamentally different entities: related but not the same. Blue/red lyrium's effect on physical races is due to its essential nature in terms of radiation: energy waves as Song.
Recall effects of blue lyrium on mortal beings and consider in terms of radiation exposure. Harmonics and resonance also involved, since the more magically sensitive the entity is, the more profound the reaction. Mages affected most dramatically (almost instant death by internal hemorrhage, according to WoTv1) so strong link to concept of infrasound + mechanical resonance likely. All entities affected depending on innate resistance and degree of exposure however: deafness, memory loss, nausea, tinnitus (ringing in ears - a different level, but still connected to hearing the "Song"). All symptoms of radiation exposure, but still points to blue lyrium as being fundamentally harmonic with natural Creation. Strength of song certainly harmful to health, but does not change the entity into something else.
Red lyrium different. Stronger. Mutative. Changes individual "Song" at DNA level. Codex describing effects of red lyrium treatment on templar strongly correlated to acute radiation poisoning: loss of hair and nails, breakdown of skin, headaches, confusion. And then becoming something else. No self left. Original song completely obliterated by new Song.
Anyway! Red lyrium. Creation probably not intentional. Think of Elvhenan at height of Pantheon's power. Almost every member’s original Duty within Pantheon twisted into promotion of worship among others' followers and developing relative strength and resistance of own. Massive pressure on Ghil at this point: demands to create physical races with stronger and stronger Will, because stronger Will = better follower, better soldier. Ghil does her best, but hits a biological roadblock with what she has on hand. Song can only be made so strong, capping out with direct manipulation of dragon blood. Elgar’nan steps in, grants her access to the primeval source of Will in original creation: Old Dragon God blood, courtesy of Sun still being held in the Void. Result of this tinkering may be kossith, or kossith may have been a product of combining races with a “beast dragon” step before. Still uncertain.
Problem is that the increasing demands of the Pantheon don’t stop there. More pressure. More demand. Ghil thinks, “Hey, all the name of Science, right?” Tweaks things a bit too far- hits a critical tipping point in tinkering with the Will in the original blood of the Sun- an amplitude / oscillation powerful enough to actively infect and change the Song of similar entities it comes in contact with. This is sundering of Song. Blue lyrium turns red. Blood of the Sun is no longer harmonic with the Song of the original Universe – literally unnatural. The kind of GMO that keeps Republicans up at night. FrankenSong.
Red lyrium is direct threat to Stone, but is not Blight yet. Can dramatically affect, but not infect races of Thedas. Conversion from red lyrium to Blight is almost certainly Magisters' doing. Would pin on Architect, if pressed. Tinkering after discovery in physical City creates human variant, virus-style. Still primarily a bloodborne disease, but now blood of physical races. Directly infectious. Darkspawn.
Completely in love with the idea of Warden joining as semi-effective vaccination! Totally brilliant. Desperately need to read Last Flight, as I think Caddius has mentioned it describes Fiona being "cured" of Warden taint with result of complete immunity. Key is definitely in there.
Anyway. Still catching up with thread- no doubt others have covered much of this more coherently. Will try to reform thoughts to add to basic wiki idea when not so feverish and preoccupied with disgusting bodily fluids.
*crawls back in bed*