Well, I have a bit of a soft spot for Bard Class
Then, when you crack the Memory Jar, your opponent takes a bunch of damage from Megrim from discarding cards, and you simply draw into more tutors, Memory Jars, and fast mana
Sure, you could be safer and only choose 2, but youll feel lousy 25% of the time when you get nothing and youll never hit the 3% Omniscience by playing it safe
Murktide Regent enters the battlefield with +1/+1 counters on it for each instant and sorcery exiled with its ability, letting you catapult it up from a 3/3 up to an 8/8 at most, though youll likely settle around a 5/5 or 6/6
Im giving this rating on the assumption that you simply cant use Ghost-Spider, though if you manage to, the card can be quite powerful
Skulk (This creature can't be blocked by creatures with greater power.) When this creature enters, target creature an opponent controls doesn't untap during its controller's next untap step