If you discarded a nonland card, put a +1/+1 counter on that creature.) Once an ability that causes a creature to connive begins to resolve, no player may take any other actions until it's done
If a creature enters with counters, those counters are included
Make use of Herald of Slaanesh to reduce the cost of your Demons, and you could be both cascading off big spells and dealing huge damage on a single cast spell
Converting those cards into extra card advantage is amazing, and you get a full turn cycle to sequence those cards into your game plan
Yeva, Natures Herald Yeva, Nature's Herald is nice in an elfball deck, but I keep cutting it from my green stompy decks
Versions of this effect that are good tend to give the stats boost up front