This is another testament to the approachability to this set
An effect would just encourage people to play as poorly as possible, since they know they'll be rewarded with more cards to draw from their deck, and more options in their s/t zone.
Point the camera at a full binder page and it recognizes card after card hands-free, keeps a running total, and never asks you to tap confirm between cards
The +1/+1 and -1/-1 counters cancel each other out
Duskmourn: House of Horror Prerelease and Draft Guide Prepare, if you dare, for a fun-filled Duskmourn: House of Horror Prerelease at your local game store
You will probably end up with some as a result of playing games and participating in certain Steam events (like the 2013 Steam Summer Sale), but you can just safely leave them in your inventory and miss out on practically nothing