Mulligans
General Mulligans
You can mulligan for almost any of your early game cards, as they will find a use no matter which type of deck you are facing. Life tap will gain you a card advantage and usually provide you with all the answers you need.
Aggro Mulligans
Keep crawler and ooze if you think you are against pirate warrior or almost any rogue deck, as they all run swashburglar.
Reno Jackson is surely not dead, and Renolock is as strong as ever in the wild format! With the new additions from Ungoro and past expansions, this deck is incredible powerful. Notable additions to the deck are Hemet, Jungle Hunter and Tar Creeper.
Early on, you should just focus on surviving. You can outvalue almost any control deck in the late game, but it can be difficult to get there. The massive amount of removal, taunts and heals should do the job, so don’t be scared to lifetap almost every turn early on.
Substitutions:
If you’re dealing with more control than aggro, blastcrystal will help you a lot more than other removal, notably Imp-losion.
The rest of these substitutions are just simple budget options if you don’t have every card for the deck
I would highly recommend using a deck tracker for Hemet, so you know exactly which cards you would be getting rid of. He is a hard card to use correctly, so only use it if you know the cards you are removing would be useless to you at that stage of the game.