Caged Sun

As Caged Sun enters, choose a color.
Creatures you control of the chosen color get +1/+1.
Whenever a land's ability causes you to add one or more mana of the chosen color, add one additional mana of that color.

Pure Reflection

Whenever a player casts a creature spell, destroy all Reflections. Then that player creates an X/X white Reflection creature token, where X is the mana value of that spell.

Dimensional Breach

Exile all permanents. For as long as any of those cards remain exiled, at the beginning of each player's upkeep, that player returns one of the exiled cards they own to the battlefield.

Howling Mine

At the beginning of each player's draw step, if Howling Mine is untapped, that player draws an additional card.

Michiko Konda, Truth Seeker

Whenever a source an opponent controls deals damage to you, that player sacrifices a permanent.

Sol Ring

Aurification

Whenever a creature deals damage to you, put a gold counter on it.
Each creature with a gold counter on it is a Wall in addition to its other creature types and has defender. (Those creatures can't attack.)
When Aurification leaves the battlefield, remove all gold counters from all creatures.

Knowledge Pool

Imprint — When Knowledge Pool enters, each player exiles the top three cards of their library.
Whenever a player casts a spell from their hand, that player exiles it. If the player does, they may cast a spell from among other cards exiled with Knowledge Pool without paying its mana cost.

Uba Mask

If a player would draw a card, that player exiles that card face up instead.
Each player may play lands and cast spells from among cards they exiled with Uba Mask this turn.

Phyrexian Processor

As Phyrexian Processor enters, pay any amount of life.
{4}, {T}: Create an X/X black Phyrexian Minion creature token, where X is the life paid as Phyrexian Processor entered.

Celestial Mantle

Enchant creature
Enchanted creature gets +3/+3.
Whenever enchanted creature deals combat damage to a player, double its controller's life total.

Omen Machine

Players can't draw cards.
At the beginning of each player's draw step, that player exiles the top card of their library. If it's a land card, the player puts it onto the battlefield. Otherwise, the player casts it without paying its mana cost if able.

Jester's Mask

Jester's Mask enters tapped.
{1}, {T}, Sacrifice Jester's Mask: Target opponent puts the cards from their hand on top of their library. Search that player's library for that many cards. That player puts those cards into their hand, then shuffles.