Akki Underling

As long as you have seven or more cards in hand, Akki Underling gets +2/+1 and has first strike.

Thoughts of Ruin

Each player sacrifices a land of their choice for each card in your hand.

Cruel Deceiver

{1}: Look at the top card of your library.
{2}: Reveal the top card of your library. If it's a land card, Cruel Deceiver gains "Whenever Cruel Deceiver deals damage to a creature, destroy that creature" until end of turn. Activate only once each turn.

Barrel Down Sokenzan

Sweep — Return any number of Mountains you control to their owner's hand. Barrel Down Sokenzan deals damage to target creature equal to twice the number of Mountains returned this way.

Death of a Thousand Stings

Target player loses 1 life and you gain 1 life.
At the beginning of your upkeep, if you have more cards in hand than each opponent, you may return Death of a Thousand Stings from your graveyard to your hand.

Deathmask Nezumi

As long as you have seven or more cards in hand, Deathmask Nezumi gets +2/+1 and has fear. (It can't be blocked except by artifact creatures and/or black creatures.)

Godo's Irregulars

{R}: Godo's Irregulars deals 1 damage to target creature blocking it.

Kemuri-Onna

When Kemuri-Onna enters, target player discards a card.
Whenever you cast a Spirit or Arcane spell, you may return Kemuri-Onna to its owner's hand.

Hand of Cruelty

Protection from white
Bushido 1 (Whenever this creature blocks or becomes blocked, it gets +1/+1 until end of turn.)

Ghost-Lit Stalker

{4}{B}, {T}: Target player discards two cards. Activate only as a sorcery.
Channel — {5}{B}{B}, Discard Ghost-Lit Stalker: Target player discards four cards. Activate only as a sorcery.

Skull Collector

At the beginning of your upkeep, return a black creature you control to its owner's hand.
{1}{B}: Regenerate Skull Collector.

Flames of the Blood Hand

Flames of the Blood Hand deals 4 damage to target player or planeswalker. The damage can't be prevented. If that player or that planeswalker's controller would gain life this turn, that player gains no life instead.

Spiraling Embers

Spiraling Embers deals damage to any target equal to the number of cards in your hand.

Honden of Night's Reach

At the beginning of your upkeep, target opponent discards a card for each Shrine you control.

Okiba-Gang Shinobi

Ninjutsu {3}{B} ({3}{B}, Return an unblocked attacker you control to hand: Put this card onto the battlefield from your hand tapped and attacking.)
Whenever Okiba-Gang Shinobi deals combat damage to a player, that player discards two cards.

Sokenzan Spellblade

Bushido 1 (Whenever this creature blocks or becomes blocked, it gets +1/+1 until end of turn.)
{1}{R}: Sokenzan Spellblade gets +X/+0 until end of turn, where X is the number of cards in your hand.

Sokenzan Renegade

Bushido 1 (Whenever this creature blocks or becomes blocked, it gets +1/+1 until end of turn.)
At the beginning of your upkeep, if a player has more cards in hand than each other player, the player who has the most cards in hand gains control of Sokenzan Renegade.

Swamp

Gnat Miser

Each opponent's maximum hand size is reduced by one.

Locust Miser

Each opponent's maximum hand size is reduced by two.

Akuta, Born of Ash

Haste
At the beginning of your upkeep, if you have more cards in hand than each opponent, you may sacrifice a Swamp. If you do, return Akuta, Born of Ash from your graveyard to the battlefield.

Goblin Cohort

Goblin Cohort can't attack unless you've cast a creature spell this turn.

Honden of Infinite Rage

At the beginning of your upkeep, Honden of Infinite Rage deals damage to any target equal to the number of Shrines you control.

Sink into Takenuma

Sweep — Return any number of Swamps you control to their owner's hand. Target player discards a card for each Swamp returned this way.

Shuko

Equipped creature gets +1/+0.
Equip {0} ({0}: Attach to target creature you control. Equip only as a sorcery.)

Kagemaro's Clutch

Enchant creature
Enchanted creature gets -X/-X, where X is the number of cards in your hand.