This one had more than the usual changes. As it's entered above is how I originally built the deck on the day of the event. It then went unplayed for most of the set's duration and when Steven and I revisited it for our series, I immediately made some changes. Without knowing Steven's deck, I pulled out Linden, Shining Armor, and Gingerbread cabin. The deck wanted to be heavy white because of the tacticians, but not heavy enough to warrant a triple white card and Linden just isn't amazing anyway. In a three colour deck, the common lands are just worse than basic lands 90% of the time, Gingerbread Cabin was just bad. Shining Armor seemed nice with the Tacticians but I think it's really for knights with more power. Also, 5 knights with two of them not coming down until turn 6 or so, just seemed short of critical mass for this card to be effective. Still might have been good, but not sad I pulled it.  This is a good example of the struggle of this deck. It had very powerful tools not quite working in concert. It was definitely not aggressive, and all three colors were contributing, but there'd never be a tipping point where I'd think "ok, now we're in our zone". It was a lot of destroy, evade, avoid control, hope for garruk. I'm still not entirely sure if there was a coherent game plan to be built here.
In place of those two, I added Curious Pair and maybe Reaper/Harvest Fear? Both were cards I don't think I'd have spotted as good on my own but by this point I knew were clearly better than what was coming out.
From there it got harder. After getting stuck with two Witchstalkers in hand and one forest, despite knowing that's a great card, I begrudgingly pulled one of those. Basically I needed to reduce my need for multiples of the same colour, and it seemed like it had to be green or black (Tacticians x3 and Resolute Rider, and the eventual need to definitely have plenty of white to handle Steven's aggressive deck with Outflank and Giant Killer). So in a sense, it was a second Witchstalker vs Syr Konrad. I knew/had been told Witchstalker was one of the best (non removal) commons, but Konrad is still better. That got me an Outflank which, admittedly, was specifically for Steven's deck. In most cases, I only needed one creature on the battlefield to make Outflank an effective kill spell. and three creatures out would kill I think anything he had except the ogre.
Nearly an hour of deliberation led to the last change which was undeniably a Steven specific change, although ultimately it didn't matter as our final game he just never drew a plains :-(
Replacing Oakhame Adversary with Signpost Scarecrow felt super dumb, but 4 toughness was extremely important against his deck. A shitty 2/4 vs a 3/1 is still a win whereas a 2/3 deathtouch card draw vs a 3/1 is a losing trade. The fact that I knew Adversary would never come in cheaper means it's probably something good players would side out in most non-green matchups anyway.
The bold move was Once Upon a Time out for another Outflank. The reasoning being: My win con isn't a creature. Once is excellent for searching for or tossing land, but there are just too many important-to-this-deck cards that it can't get me. Using outflank on the little firebreather early game can be enough of a wrench in Steven's deck's game plan that it may never recover.
Would love to know if these last two swaps check out in the minds of better players.

Final deck list that effectively won by default in the last game of the last match was:

1 Castle Ardenvale
3 Ardenvale Tactician // Dizzying Swoop
1 Curious Pair // Treats to Share
1 Epic Downfall
1 Faerie Guidemother // Gift of the Fae
1 Fierce Witchstalker
1 Garruk, Cursed Huntsman
1 Giant Killer // Chop Down
1 Golden Egg
1 Heraldic Banner
2 Outflank
2 Outmuscle
1 Piper of the Swarm
1 Reaper of Night // Harvest Fear
1 Reave Soul
1 Resolute Rider
1 Return to Nature
1 Savvy Hunter
1 Signpost Scarecrow
1 Syr Konrad, the Grim
1 Wildborn Preserver