First of all, Great Thanks to the author, it is a very efficient deck against a wide range of opponents.
I have now played around a 100 games with SPlat, some arena farming some FG farming. The problem opponents are those loaded with purifies, and those with many creatures and multi-empathy healing (such as Elidnis, Fire Queen, Ferox). Multiple miracles can also be a problem making you deck out.
However, you can learn which FGs to skip, and you can also give up arena games if you see multiple empathy cards come up for many creatures. Overall you probably get close to 50% win rate against FGs and platinum arena, and somewhat higher against gold arena (I got several special spins from gold).
On the other hand, what annoys me are the games when I simply do not pull any scorpion OR momentum in the first half of the deck. The RNG can really make me mad
If I have 5+5 of them in the deck, holding back all 5 of a kind into the second half of the deck ought to be a very low probability event but it happens way too often! So I modded the deck this way:
Hover over cards for details, click for permalink
5rt 5rt 5rt 5rt 5rt 5rt 6rm 6rm 6rm 6rm 6rm 6rm 6rt 6rt 6rt 6rt 6rt 6rt 74a 74a 74a 74a 74a 74a 7q0 7q0 7q0 7q0 7q0 7q0 8pl
With this version I usually get both scorpion and momentum early enough (first 2-3 turns, i.e. within 10 cards), BUT the the RNG can still screw me up by not giving me any time tower for a while -- which is again crazy as I still have 6 in the deck, so it is the same probability as all other cards (5x6). I might have to swap 1-2 divinity to time tower to fix this problem.