Alright, I've looked over your thoughts. I'm not good enough with Purple to say how you could have won this, but hopefully something I say here could help.
Back on Turn 1 you decided to go for a Reaver play to see if you could make it work, but you also considered going for Slow Time Generator. A Past plan may have been better for leveraging your early economy, but it's hard to say since I haven't tried either myself. At the very least it would have given you large bodies faster since you wouldn't have to wait for them.
Also, while I've definitely gone into games saying "I'm going to tech these specific cards," and I've even won some of them that way, there's something to be said for a plan that emerges from the board position over time. That's what I did this time, since I knew that trying to plan out too far in advance would get me in trouble due to being rusty. If you read my thoughts, I didn't decide on the plan I ended up winning with (Earthquake) until Turn 4 (though I'd been thinking about it on Turn 3), and that was after I'd already teched a Mind-Parry Monk to ensure Rook could stay maxed long enough for that to work and a Young Lightning Dragon to keep the pressure on. While
Your initial tech plan had Reaver coming before Omegacron, and I understand that from the perspective of trying to make Reaver work, but perhaps swapping them would have been more effective? A Reaver might have a better chance of getting its lockdown started if the opponent is desperately fending off a 9/7... More interesting to me is that you went with Argonaut and Seer for your first tech. Did you consider Stewardess of the Undone? For that matter, if you were going for a strategy involving forecast, you could have gone all in with Knight of the Conclave.
You did notice the risk of True Power of Storms as early as Turn 2, but that was a feint more than anything -- I knew that I wouldn't be able to prevent Origin Story from getting Grave, so I was just using him as a large body that could cast Reversal.
I think Turn 3 was a critical point. I'd just killed Geiger and got Grave dangerously close to max level before you had Origin Story in your deck. Worse, I also had three units to support him while you only had Mox. At that point, two things seem like mistakes here:
- You continued going with the Reaver plan, despite the pressure I was putting on you. Your plan was to use Reaver to lock down my board, but at this point I was already locking you down. Pivoting to either Past for cheap but strong units (including a $1 flyer) may have been better. Pivoting to Present for various large units and in particular Hyperion's haste may have been better still.
- You still rushed Tech II, again despite the pressure I was putting on you. To be fair, if you'd managed to get Reaver out there before your Tech II fell it might have been able to do something... But you were betting on a 50/50 chance for getting it down on Turn 4, and that failed you. Because of that, and because Reaver was the only Tech II you had in your deck, it was a waste of 4 gold that could have been spent on defense.
If you read my thoughts for Turn 4 you can see that I was not only expecting Origin Story, in a sense I was counting on it. I had invested exactly 6 gold into Grave ($2 to summon him, $2 to midband him a turn later, and $2 to max him the turn you played Origin Story). That gold was able to kill your Fading Argonaut ($2) and Argonaut ($3) before he was removed.
Meanwhile, the cost to cast Origin Story on him was... also 6 gold ($2 to summon Prynn, $3 to cast the spell, $1 for Resist). What did that $6 get you? Well, it did remove a max-level hero, which is good, and you were left with a 1/3 hero afterward. However, all told Grave cost you $5 "in damages" and the same $6 to remove that I spent to get him there, so while it would have been nice to keep him around longer, I was happy to see you spend the money to remove him instead of on things that could threaten my position.
Perhaps the draws you got made that your best play, but I didn't find it to be that bad. Honestly, the Mox killing Sparring Partner set me back more!
I could go on, but I think everything from there is clear enough. The overarching theme of why you lost is sticking too rigidly to a single plan, rather than adapting to what's happening on the board. There are some game plans that can work in a solitaire-esque way, but those tend to be strong enough that the opponent is forced to react to them -- and it would appear that early Reaver isn't quite that.