I used the 500hp EM deck in the OP twice previously. The first game I won, but just barely; I think I only had one or two cards left in my deck, and I burned every miracle I had. The second game I decked out, and would have won with only 1 more card in deck.
Using that knowledge, I took the original deck and added 6x upped sundial 4x earth pend, and it's big enough to work without losing any of the original concept. Your deck is then big enough to last if Octane clogs his hand early. You get the option of drawing with sundials (if you know you'll be okay drawing the extra) or simply use them as either explosion fodder (to clear Octane's hand, as he will not explode a pend unless he has 2+ explosions in hand) or to block one round of attacks, all of which are good things.
Today I got an Octane prediction, used the modification above, and it worked great. I drew with every non-exploded sundial (I think 4 or 5) and still had 8 cards in deck. (so I'd have won even without them, but with only about 2-3 cards in deck) The sundials also reduced the damage I took, and I was in no danger the entire time. I only had to play one miracle to stay alive, plus the 2nd to get a 500 EM at the end.