Ah yes, the mighty failbaddon, the man who has never actually succeeded in a black crusade, and, by recent reports, has no arms. (Yes, we know the joke is done to death.) Uz orkz is gunna have a reel gud time 'ere. But no really, Abaddon being the leader of chaos isn't really a statement that chaos is going to do well. As scary as he may seem, he's got the worst track record in regards to actual conquest.
Seriously everyone that is saying that Abbadon did nothing but fail is wrong in my not so humble opinion Every black crusade was aimed at a specific objective. Be it the gathering of massive star killing weapons or forgotten lore, weapons and things like that. The objective of the black crusades was never to conquer Tera. At least not yet. But to solidify Abbadons leadership and to gain new shiny toys. Personally I think Abaddon is a fine commander. And the greatest threat to the imperium. ( Asides from the nids )
Well you try giving orders to a bunch of crazy fanatics that all have their own agenda and are equally fine with failing or succeeding in their missions as long as there is blood shed and confusion. Horus had it easy, he just had to show how much more fun it was to do things his way. His forces were already used to following orders. Abbadon is working at a time when his forces already know how much fun it is to ignore orders and get lost in the maelstrom.
Personally I would have thought that when the Imperial Church was officially established, Lorgar should have led the Word Bearers from the Great Eye and loudly proclaimed 'I was right! I knew he was a god all along and no-one believed me!'. He should have then taken charge of the Chaos Legions: W40k would be a very different place.
I'm embarassed for Sharks and their giant pee bodies. Makes you wonder why touching their nose tip makes them spasm.