Have

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Tribute Mage

When this creature enters, you may search your library for an artifact card with mana value 2, reveal that card, put it into your hand, then shuffle.

Urza's Saga

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — This Saga gains "{T}: Add {C}."
II — This Saga gains "{2}, {T}: Create a 0/0 colorless Construct artifact creature token with 'This token gets +1/+1 for each artifact you control.'"
III — Search your library for an artifact card with mana cost {0} or {1}, put it onto the battlefield, then shuffle.

Spellbook

Unstable Amulet

When this artifact enters, you get {E}{E} (two energy counters).
Whenever you cast a spell from anywhere other than your hand, this artifact deals 1 damage to each opponent.
{T}, Pay {E}{E}: Exile the top card of your library. You may play it until you exile another card with this artifact.

Hedron Archive

{T}: Add {C}{C}.
{2}, {T}, Sacrifice this artifact: Draw two cards.

Simian Sling

Equipped creature gets +1/+1.
Whenever this creature or equipped creature becomes blocked, it deals 1 damage to defending player.
Reconfigure {2} ({2}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Crumbling Necropolis

This land enters tapped.
{T}: Add {U}, {B}, or {R}.

Temple of the False God

{T}: Add {C}{C}. Activate only if you control five or more lands.

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Clockwork Percussionist

Haste
When this creature dies, exile the top card of your library. You may play it until the end of your next turn.

Arcane Signet

Crosis's Attendant

{1}, Sacrifice this creature: Add {U}{B}{R}.

Tormentor's Helm

Equipped creature gets +1/+1.
Whenever equipped creature becomes blocked, it deals 1 damage to defending player.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Ghyrson Starn, Kelermorph

Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)
Three Autostubs — Whenever another source you control deals exactly 1 damage to a permanent or player, Ghyrson Starn deals 2 damage to that permanent or player.

Mishra, Artificer Prodigy

Whenever you cast an artifact spell, you may search your graveyard, hand, and/or library for a card with the same name as that spell and put it onto the battlefield. If you search your library this way, shuffle.

Possibility Storm

Whenever a player casts a spell from their hand, that player exiles it, then exiles cards from the top of their library until they exile a card that shares a card type with it. That player may cast that card without paying its mana cost. Then they put all cards exiled with this enchantment on the bottom of their library in a random order.

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Mindmoil

Whenever you cast a spell, put the cards in your hand on the bottom of your library in any order, then draw that many cards.

Ob Nixilis, Captive Kingpin

Flying, trample
Whenever one or more opponents each lose exactly 1 life, put a +1/+1 counter on Ob Nixilis. Exile the top card of your library. Until your next end step, you may play that card.

Dormant Volcano

This land enters tapped.
When this land enters, sacrifice it unless you return an untapped Mountain you control to its owner's hand.
{T}: Add {C}{R}.

Guildless Commons

This land enters tapped.
When this land enters, return a land you control to its owner's hand.
{T}: Add {C}{C}.

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Reflecting Pool

{T}: Add one mana of any type that a land you control could produce.

Trinket Mage

When this creature enters, you may search your library for an artifact card with mana value 1 or less, reveal that card, put it into your hand, then shuffle.

Obelisk of Grixis

Trophy Mage

When this creature enters, you may search your library for an artifact card with mana value 3, reveal it, put it into your hand, then shuffle.

Neera, Wild Mage

Whenever you cast a spell, you may put it on the bottom of its owner's library. If you do, reveal cards from the top of your library until you reveal a nonland card. You may cast that card without paying its mana cost. Then put all revealed cards not cast this way on the bottom of your library in a random order. This ability triggers only once each turn.

Price of Knowledge

Players have no maximum hand size.
At the beginning of each opponent's upkeep, this enchantment deals damage to that player equal to the number of cards in that player's hand.

Rakdos Roustabout

Whenever this creature becomes blocked, it deals 1 damage to the player or planeswalker it's attacking.

Thought Vessel

Vexing Bauble

Whenever a player casts a spell, if no mana was spent to cast it, counter that spell.
{1}, {T}, Sacrifice this artifact: Draw a card.

Coral Atoll

This land enters tapped.
When this land enters, sacrifice it unless you return an untapped Island you control to its owner's hand.
{T}: Add {C}{U}.

Everglades

This land enters tapped.
When this land enters, sacrifice it unless you return an untapped Swamp you control to its owner's hand.
{T}: Add {C}{B}.

Arjun, the Shifting Flame

Flying
Whenever you cast a spell, put the cards in your hand on the bottom of your library in any order, then draw that many cards.