AHC: Switch the reputations of the Komnenoi and the Angeloi

With a PoD of Alexios I's ascension to the throne in 1081, your challenge is to make the Komnenmoi dynasty remembered largely as a string of inept failures, while the Angeloi dynasty as energetic and capable.

Due to butterflies, of course, the Angeloi aren't going to show up in the same way, so the secondary challenge is ensuring that the descendants of the commander of the Byzantine fleet in Sicily in 1081 still find their way onto the throne.
 
Let's say Andronikos I is overthrown by Isaac Angelos but manages to flee Constantinople.

While this is happening (mid 1185), the Norman invasion of the Eastern Roman Empire is in full swing and Thessaloniki, second city of the Empire, was just conquered and horrifyingly sacked (bonus: the incompetent defender of Thessaloniki was also a Komnenos).

So somehow Andronikos links up with the Normans and promises them the XII century equivalent of a billion dollars to help him take back the throne. Helped by infighting and instability in the Empire, the Normans and Andronikos enter Constantinople in 1186. The increasingly paranoid Emperor Andronikos introduces a reign of terror which makes his earlier exploits look positively benevolent, setting out to brutally murder the aristocracy in general and the Angeloi in particular. But the Normans themselves are getting less reliable and more hostile every day as Andronikos finds out he doesn't actually have the money he needs. At some point he attempts to drive the Normans out with force, but it backfires, and we get an early Sack of Constantinople and temporary destruction of the Byzantine Empire in late 1186 or early 1187.

After all that, Andronikos I Komnenos is reviled as a callous bastard and a madman. He's remembered chiefly as the man who joined the Westerners against his own realm, won the throne with their aid, and then provoked them into the Sack of Constantinople, slaughtering thousands and leaving the empire scarred for centuries. His struggle against the power of the nobility is referred to universally in terms of "tyranny", "brutality", "repression", and as a bonus he's probably blamed for the Bulgarian revolt too.

Meanwhile, Isaac II Angelos has ruled for a grand total of one year, and thus never had the time to show off his worst qualities. He is considered a pretty cool guy who stood up to the tyranny of Andronikos, tried to defend the Empire against the western menace and unfortunately died in this unfair fight. The Angeloi were decent folk and innocent martyrs of the last months of Andronik's reign of terror.



...seriously though this is a tough AHC. Even in the scenario outlined above (which is by no means perfect), only the last of the Komnenoi gets a ruined reputation. It will taint the dynasty as a whole, but not enough to make everyone forget their earlier achievements.
 
That's as good as an idea can get really. The Komnenoi are just better stock, it's hard to make them do that horribly.
 
The Komnenoi are just better stock, it's hard to make them do that horribly.

True.
Though it's just as hard to make the other dynasty do well. I don't believe in inherently bad stock, but the history of the Angeloi almost makes me believe. When a family has an unbroken string of selfishness, incompetence, treason and hypocrisy from the 1180s to the 1450s, it's difficult to imagine them in any kind of a positive context.
 
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