Removing 8 cards will be challenging and, to make it easier, I recommend that you look for cards that do the same effect, such as "you gain X life, whenever a creature ETB's", and remove some of them, as this will allow you to keep your important and less redundant cards in your deck
If your opponent refuses to play at a reasonable pace, call a judge
If you pull a card you love, you can have the real thing shipped directly to you
This list also includes cards that "hose" that creature type, I decided to leave that in because it's potentially interesting
In particular youll want to remember the letter Z will let you undo an action, which is particularly helpful if youre adding mana to your mana pool but decide you dont want to do that yet