King Maegor wasn't truly Mad until his mother had him Reanimated.

[Robb_Warged]

Wonder if Jon will be similar

[BronnBlackwater]

It's plausible as he certainly was obsessed with his war against the faith militant.

[Ser Joe the Unknighted]

I thought he took a turn darker after he was revived. I didn't get really bloody with the faith until he woke. I don't think it really matters whether Anys and Maegor were sons of Aegon. They are just as much Targaryens.

[Alester Florent]

In all honesty I'm kind of disappointed in the somewhat one-note portrayal of Maegor in all the sources that give us any detail on him (from what I hear of Sons of the Dragon, anyway: I haven't read it myself) - and indeed I found that much of AWoIaF actually followed a similar pattern at least on the surface. I don't think it would be hard to introduce a bit more nuance into his character without necessarily making him much more sympathetic.

The idea that he was a strong and ruthless man, but not a sociopathic mass murderer, before his clonk on the head, for instance, could go some way to addressing that. Likewise I think it would be interesting to explore the idea that he was very loyal to Aenys while he lived, but wasn't prepared to tolerate dissent or weakness after his brother died. That there was a reason why much of the realm initially remained loyal to him, and was only later driven away by his madness. And further that his actions in smashing the Faith Militant were essential to Jaehaerys's later reconciliation with the Faith: that as far as the realm was concerned his reign was like a terrible medicine that nearly killed the patient but ultimately left it the stronger.

But no, it seems he was killing animals from an early age and all the signs of nutjobbery should have been there from the outset. The WoIaF introducing the stories of him butchering his nephews was also a bit of a disappointment. Still, it's not too late to patch him up a bit.

I don't think it really matters whether Anys and Maegor were sons of Aegon. They are just as much Targaryens.

Well, they're still Targaryens, but they're not as much Targaryens, since if they were Aegon's sons they'd be 100% Targ (at least, counting Aerion's children as full Targs even though they were only 75% Targ) whereas if they were only the children of Aegon's sisters they'd be 50% Targ. Unless Maegor was an immaculate conception in which case he'd still be full Targ.

[Lord Varys]

Well, Maegor actually was loyal to Aenys until he married Alys Harroway and caused trouble for the Crown and dynasty this way. He put down Jonos Arryn's rebellion and apparently served Aenys faithfully and loyal as Hand from late 37-39 AC. The brothers seem to have gotten along quite well until the polygamy crisis struck.

Until he claimed the throne Maegor had never threatened or harmed any of Aenys' kin, and it may actually be that he and Visenya did not intend to deal with Prince Aegon the way they did as it was Aegon who later challenged Maegor's kingship, but there is no excuse for the treatment of Prince Viserys after Alyssa's escape - however, we don't actually know how Alyssa behaved in the years 42-44 AC and how she helped the cause of her son Aegon, or how she worked to undermine Maegor. Prince Aegon must somehow gotten hold of his father Aenys' dragon Quicksilver, for instance.

Nothing suggests that Maegor was serial killer type of guy. He just really liked inflicting pain and was a sort of brooding control freak. He was a great warrior but had no friends - despite the fact that he was the son of the king. That is a very bad sign.

Gyldayn thinks both Aenys and Maegor sucked as kings, but Aenys had the advantage of having charisma and charm and being good-willed - Maegor had nothing of that. While Aenys could have been a decent king in a period of peace if a strong Hand had helped him rule (like Aerys I had with Bloodraven or Aegon III and his sons with Prince Viserys) Maegor would have sucked in any era, I think.

Putting down the Faith Militant was a thing any Targaryen monarch had to do to continue the rule (and the incest custom) but Aenys did not have the stomach for that - which essentially seems to be why Visenya murdered him - while Maegor clearly overdid it and eventually turned all the Realm against him. Going in full-blown polygamy mode and alienating/executing all his allies certainly wasn't a good way to keep the throne.

Aenys' downfall is also caused by the fact that he first alienates his family (he exiles Maegor over the Alys affair, and then alienates Visenya when he names Aegon Prince of Dragonstone in Maegor's place) but the real blow is the continuation of the incest. Maegor's downfall seems to begin with the black bride thing in 47 AC which leads to more abominations, and the subsequent downfall and execution of Tyanna of the Tower who most likely was one of Maegor's closest allies and a pillar of his power.