One thing is for certain in this format, and that is that nothing is for certain.
In last year's Invasion block team Rochester, the strategy was all about winning the mirror matches. Black always fought black in seat A, blue/white/red often fought itself in B, and head-to-head five-color-green battles took place between C-seat competitors. You could often get by simply by knowing which cards were good in the mirror.
But this year, the strategy seems to be about avoiding mirror matches, and there isn't one clear-cut way to do so.
After watching a round of drafts and talking to eliminated players Mike Flores, Tomi Walamies, and Andrew Cuneo, here's what I put together:
Seat B is almost always either blue/white or blue/green. Blue/white seems to be the best deck for seat B, as it is probably the color combination with the most synergy and raw power. Amazing defense, utility, and fliers give it the weapons to beat just about anything. It's hard to see what blue/green has to offer, other that huge thresholded monsters. It can't kill utility creatures, but maybe the big monsters are enough. The jury is still out on whether or not blue/white can beat blue/green or vice versa. I think green ends up in this seat by default a lot of the time. The one combo that can consistently beat blue/white is black/blue. Cabal Torturer is the MVP in that matchup, killing Looters and Healers. Teams that eschew black in A tend to put blue/black in B.
So what would I do? I would definitely play to the pack's strengths, and always put black in seat A and white in seat C. Black/red seems like a great color combo, and that would probably be my first choice in A, and I'd have no problem forcing it. In seat C I'd react, drafting white/red if my opponent was blue/green or blue/white, and white/blue or white/green if my opponent was green/red. If I couldn't react properly because my opponent wasn't playing one of those combinations, I'd default to white/red. That leaves B, which would probably be blue/green most of the time with the option of splashing black for cards like Ghastly Demise that aren't good in the black mirror. Lost in Thought and Psionic Gift would be high picks to deal with the inevitable troublesome Looters and Healers.