Putrefy

Destroy target artifact or creature. It can't be regenerated.

The Eldest Reborn

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Each opponent sacrifices a creature or planeswalker of their choice.
II — Each opponent discards a card.
III — Put target creature or planeswalker card from a graveyard onto the battlefield under your control.

Epic Proportions

Flash
Enchant creature
Enchanted creature gets +5/+5 and has trample.

Snow-Covered Forest

Sol Ring

Grim Backwoods

{T}: Add {C}.
{2}{B}{G}, {T}, Sacrifice a creature: Draw a card.

Overwhelming Stampede

Until end of turn, creatures you control gain trample and get +X/+X, where X is the greatest power among creatures you control.

Vivid Grove

This land enters tapped with two charge counters on it.
{T}: Add {G}.
{T}, Remove a charge counter from this land: Add one mana of any color.

Snow-Covered Swamp

In Garruk's Wake

Destroy all creatures you don't control and all planeswalkers you don't control.

Ikra Shidiqi, the Usurper

Menace
Whenever a creature you control deals combat damage to a player, you gain life equal to that creature's toughness.
Partner (You can have two commanders if both have partner.)

Myriad Landscape

This land enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice this land: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

Colossification

Enchant creature
When this Aura enters, tap enchanted creature.
Enchanted creature gets +20/+20.

Vivid Marsh

This land enters tapped with two charge counters on it.
{T}: Add {B}.
{T}, Remove a charge counter from this land: Add one mana of any color.

Vulturous Zombie

Flying
Whenever a card is put into an opponent's graveyard from anywhere, put a +1/+1 counter on this creature.

Bear Umbra

Enchant creature
Enchanted creature gets +2/+2 and has "Whenever this creature attacks, untap all lands you control."
Umbra armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Leyline Prowler

Deathtouch, lifelink
{T}: Add one mana of any color.

Guardian Project

Whenever a nontoken creature you control enters, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.