Advice on route to take, Aeyrs succeeds in the Wildfire Plot
Rhaegar lost the trident, as per canon. When Tywin moves to sack Kings Landing, Jaimie is in the process of killing Aerys and hunting down the Alchemists. He is unsuccessful in killing them all, some escape and distribute the orders. The Order of Alchemists is torn, the loyalists wanting to carry out the orders, others wanting to scrap them. They split, some attempting to set the wildfire off, some trying to stop them, some fleeing, etc.
The first cache to go off is in the Dragonpit, the sane alchemists prioritizing the Red Keep, the Sept of Baelor, and other population dense areas. At first there is fear and confusion, with fire spreading from the Dragonpit, however, when the second cache goes off, panic sets in. Riots, fleeing crowds, etc. No longer the scariest thing, Tywin's forces, still pouring in face crowds in the 10s of thousands charging towards them, trying to escape. He quickly retreats, but most of the forces already through the gate are trampled by the unstoppable crowds. Tywin loses 5 of his 12,000.
50,000 died from the initial explosions, with the Dragonpit gone, and around 1/4 of the city around it destroyed. A few other caches in different places went off, but the sane alchemists managed to put them out.
30,000 died from spreading fire
20,000 died to the spreading fumes
30,000 died in the riots to escape
50,000 escaped the city in the first weak
80,000 more escaped in the first month
240,000 remained in Kings Landing when it was finally put to order by Eddard Stark
Once the rebels arrived and put the city to order, they realised that Elia, Aegon, Rhaenys and Jaimie were gone. Jaimie had successfully rescued them and made it out and to Dragonstone, the Mountain and his men had been delayed and never made it to the keep. From there, the whole Royal family moved with the Royal Fleet to Dorne. The delay also was long enough for Stannis to be forced to surrender Storm's End or Renly would have died.
On the first day of explosions, a red streak appeared in the sky, originally it was not known what it meant. Soon everyone realised, it heralded the return of magic.
I am stuck on what happens from here. Many paths: does Mace turn coat? Jon is born, Lyanna dies, what do the Kingsguard do? Does Dorne submit to Baratheon rule in exchange for peace? Do Dorne and the rest of the Realm enter a cold war, with Dorne not submitting or declaring independence, and Robert's allies uncertain of invasion? Or does war begin, and Dorne successfully retain their independence?
The main aim of the story is a much higher fantasy, more powerful and more common magic (if still erratic and hard to control), interfering gods (though not too extreme), etc. I am uncertain when/if dragons return.
Additionally, i have a completely different story in which the premise is dragons returning at Summerhall for Aegon the Unlikely, but i am leaning towards this. Thoughts and discussion is welcome.