Training Grounds

Activated abilities of creatures you control cost {2} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Marneus Calgar

Double strike
Master Tactician — Whenever one or more tokens you control enter, draw a card.
Chapter Master — {6}: Create two 2/2 white Astartes Warrior creature tokens with vigilance.

Heartstone

Activated abilities of creatures cost {1} less to activate. This effect can't reduce the mana in that cost to less than one mana.

Scholar of Athreos

{2}{B}: Each opponent loses 1 life. You gain life equal to the life lost this way.

K'rrik, Son of Yawgmoth

({B/P} can be paid with either {B} or 2 life.)
Lifelink
For each {B} in a cost, you may pay 2 life rather than pay that mana.
Whenever you cast a black spell, put a +1/+1 counter on K'rrik, Son of Yawgmoth.