These are the most difficult to come by and are often game-changing
Mana from Interdimensional Web Watch's last ability may be spent on any spells cast from exile, not just spells cast from exile via its first ability
I also think a good rule of thumb for this format is to have at least six, if not more, two-drops - whether they be creatures like Thought Shucker or removal spells like Savor
Many people in my playgroups built Tamiyo, Inquisitive Student on release, because they love Tamiyo as a character
Its worth stressing that these dont offer any additional cards you wont find in the standard versions, but give every single card a foil treatment
If you have no cards in hand as Case of the Crimson Pulse's first ability resolves, you won't discard a card, but you will still draw two cards