Nekusar, the Mindrazer

At the beginning of each player's draw step, that player draws an additional card.
Whenever an opponent draws a card, Nekusar, the Mindrazer deals 1 damage to that player.

Anvil of Bogardan

Players have no maximum hand size.
At the beginning of each player's draw step, that player draws an additional card, then discards a card.

Windfall

Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Howling Mine

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

Rhystic Study

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

Fate Unraveler

Whenever an opponent draws a card, Fate Unraveler deals 1 damage to that player.

Mindcrank

Whenever an opponent loses life, that player mills that many cards. (Damage causes loss of life.)

Syr Konrad, the Grim

Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent.
{1}{B}: Each player mills a card. (They each put the top card of their library into their graveyard.)

Cursed Rack

As Cursed Rack enters, choose an opponent.
The chosen player's maximum hand size is four.