War's Toll

Whenever an opponent taps a land for mana, tap all lands that player controls.
If a creature an opponent controls attacks, all creatures that opponent controls attack if able.

Condemn

Put target attacking creature on the bottom of its owner's library. Its controller gains life equal to its toughness.

Marisi, Breaker of the Coil

Your opponents can't cast spells during combat.
Whenever a creature you control deals combat damage to a player, goad each creature that player controls. (Until your next turn, those creatures attack each combat if able and attack a player other than you if able.)

Serra's Blessing

Creatures you control have vigilance. (Attacking doesn't cause them to tap.)

Keensight Mentor

When Keensight Mentor enters, put a vigilance counter on target non-Human creature you control.
{1}{W}, {T}: Put a +1/+1 counter on each creature you control with vigilance.

Shiny Impetus

Enchant creature
Enchanted creature gets +2/+2 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, you create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Warmonger Hellkite

Flying
All creatures attack each combat if able.
{1}{R}: Attacking creatures get +1/+0 until end of turn.

Choking Fumes

Put a -1/-1 counter on each attacking creature.

Brave the Sands

Creatures you control have vigilance.
Each creature you control can block an additional creature each combat.

Marrow Shards

({W/P} can be paid with either {W} or 2 life.)
Marrow Shards deals 1 damage to each attacking creature.

Grand Melee

All creatures attack each combat if able.
All creatures block each combat if able.

Martial Impetus

Enchant creature
Enchanted creature gets +1/+1 and is goaded. (It attacks each combat if able and attacks a player other than you if able.)
Whenever enchanted creature attacks, each other creature that's attacking one of your opponents gets +1/+1 until end of turn.

Alert Heedbonder

Vigilance
At the beginning of your end step, you gain 1 life for each creature you control with vigilance.

Defensive Formation

Rather than the attacking player, you assign the combat damage of each creature attacking you. You can divide that creature's combat damage as you choose among any of the creatures blocking it.

Frondland Felidar

Vigilance
Creatures you control with vigilance have "{1}, {T}: Tap target creature."

Curse of Stalked Prey

Enchant player
Whenever a creature deals combat damage to enchanted player, put a +1/+1 counter on that creature.