Timetwister

Each player shuffles their hand and graveyard into their library, then draws seven cards. (Then put Timetwister into its owner's graveyard.)

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Rhystic Study

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Shiva, Warden of Ice

(As this Saga enters and after your draw step, add a lore counter.)
I, II — Mesmerize — Target creature can't be blocked this turn.
III — Cold Snap — Tap all lands your opponents control. Exile Shiva, then return it to the battlefield (front face up).

Jill, Shiva's Dominant

When Jill enters, return up to one other target nonland permanent to its owner's hand.
{3}{U}{U}, {T}: Exile Jill, then return it to the battlefield transformed under its owner's control. Activate only as a sorcery.