Hi!
Just wanted to add my secret tech in dealing with colossus (which i didn't really get to use since i didn't play against a deck with colossus and couldn't beat patronvoidmage to make it to top 4 and face the colossus deck) is magus of the unseen.
I opted not to play sigil of sleep in my sideboard, and played 2 maguses instead. Also, one card that many people may have overlooked when trying to deal with a darksteel colossus is none other than... sculpting steel. It's a 3 mana for a colossus, sure it doesn't kill your opponent's colossus, but for 3 mana you can get an indestructable colossus yourself to deal with his, or trade blows. It's only 3 mana, so it's playable in fish and it's much easier to resolve too, and it's also good in case you want to sculpt a triskelion, platinum angel or who knows what else, even a crucible, if your opponent has one and you haven't drawn yours.
So, just to keep in mind, 2-3 sculpting steels in the sideboard may not be a bad idea for fish.
p.s. I was the guy who lost to patronvoidmage in top 8, even though i won game 1 while holding 3 null rods in my hand the whole game.
