Bane's Contingency

Counter target spell. If that spell targets a commander you control, instead counter that spell, scry 2, then draw a card.

Elminster

Whenever you scry, the next instant or sorcery spell you cast this turn costs {X} less to cast, where X is the number of cards looked at while scrying this way.
+2: Draw a card, then scry 2.
−3: Exile the top card of your library. Create a number of 1/1 blue Faerie Dragon creature tokens with flying equal to that card's mana value.
Elminster can be your commander.

Heap Gate

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{1}, {T}, Tap an untapped Gate you control: Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Vision of the Unspeakable

Flying, trample
Vision of the Unspeakable gets +1/+1 for each card in your hand.

Behold the Unspeakable

(As this Saga enters and after your draw step, add a lore counter.)
I — Creatures you don't control get -2/-0 until your next turn.
II — If you have one or fewer cards in hand, draw four cards. Otherwise, scry 2, then draw two cards.
III — Exile this Saga, then return it to the battlefield transformed under your control.

Behold the Unspeakable // Vision of the Unspeakable

Founding the Third Path

Read ahead (Choose a chapter and start with that many lore counters. Add one after your draw step. Skipped chapters don't trigger. Sacrifice after III.)
I — You may cast an instant or sorcery spell with mana value 1 or 2 from your hand without paying its mana cost.
II — Target player mills four cards.
III — Exile target instant or sorcery card from your graveyard. Copy it. You may cast the copy.

Patch Up

Return up to three target creature cards with total mana value 3 or less from your graveyard to the battlefield.

Timely Ward

You may cast Timely Ward as though it had flash if it targets a commander.
Enchant creature
Enchanted creature has indestructible.

Volcanic Fallout

This spell can't be countered.
Volcanic Fallout deals 2 damage to each creature and each player.

Invoke the Winds

Gain control of target artifact or creature. Untap it.

Loxodon Warhammer

Equipped creature gets +3/+0 and has trample and lifelink.
Equip {3}

Backstreet Bruiser

Defender
As long as there are two or more counters among creatures you control, Backstreet Bruiser can attack as though it didn't have defender.

Bathe in Gold

Create a Treasure token. (Then exile this card. You may cast the creature later from exile.)