Nivix Cyclops to test. This is one of those weird UR decks that doesn't look like an aggro deck on the surface but actually is, due to the interactions between the Cyclops, Young Pyromancer and Guttersnipe with all the cantrip effects.
I had a couple slots available and was trying out Chameleon Colossus and Woodland Changeling to see if their Changeling ability would come in handy with the Reaper King. I didn't want to buy more Scarecrones and I didn't have more Collective Restraints, coupled with not a lot of creatures, made me want to lean into more creatures.
We had about four, maybe five matchups and one thing became very clear: Collective Restraint is a Very Big Deal against aggro decks. If I got one down with 9 or more life available, I could grind out a win. If not, I died under a wave of UR beats.
Worldly Council proved itself to be a champ here. I came away from these games convinced that I should be running four. While that puts the deck to 61 cards, the opportunity to dig into my deck that far is too good to ignore.
The duds were the Changelings. While great under Reaper King, they didn't do much else. I should just find more Scarecrows to add because these just didn't provide enough synergy. The Changelings trigger Reaper King and I can sacrifice them to Scarecrone-but I can't bring them back with Scarecrone.