Mind Stone

{T}: Add {C}.
{1}, {T}, Sacrifice this artifact: Draw a card.

Ruby Medallion

Red spells you cast cost {1} less to cast.

Kratos, God of War

Double strike
All creatures have haste.
At the beginning of each player's end step, Kratos deals damage to that player equal to the number of creatures that player controls that didn't attack this turn.

Maximum Carnage

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Until your next turn, each creature attacks each combat if able and attacks a player other than you if able.
II — Add {R}{R}{R}.
III — This Saga deals 5 damage to each opponent.

Sol Ring

Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

Crawlspace

No more than two creatures can attack you each combat.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

Arena of Glory

This land enters tapped unless you control a Mountain.
{T}: Add {R}.
{R}, {T}, Exert this land: Add {R}{R}. If that mana is spent on a creature spell, it gains haste until end of turn. (An exerted permanent won't untap during your next untap step.)

Archetype of Aggression

Creatures you control have trample.
Creatures your opponents control lose trample and can't have or gain trample.

Urabrask the Hidden

Creatures you control have haste.
Creatures your opponents control enter tapped.

Castle Embereth

This land enters tapped unless you control a Mountain.
{T}: Add {R}.
{1}{R}{R}, {T}: Creatures you control get +1/+0 until end of turn.