Whenever you gain life, each opponent loses 1 life. {1}, Sacrifice another creature: Dina, Soul Steeper gets +X/+0 until end of turn, where X is the sacrificed creature's power.

At the beginning of your end step, target opponent gains control of up to one target creature you control. Put two +1/+1 counters on it and tap it. It's goaded for the rest of the game and it gains "This creature can't be sacrificed." (It attacks each combat if able and attacks a player other than you if able.) Whenever a creature you own but don't control attacks, you draw a card.

Whenever you sacrifice a permanent, put a +1/+1 counter on Juri, Master of the Revue. When Juri dies, it deals damage equal to its power to any target.

Landfall — Whenever a land enters the battlefield under your control, you gain 1 life and draw a card.

If a creature dying causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time. Creature tokens you control have vigilance and lifelink.

Activated abilities of creatures you control cost {X} less to activate, where X is Agatha of the Vile Cauldron's power. This effect can't reduce the mana in that cost to less than one mana. {4}{R}{G}: Other creatures you control get +1/+1 and gain trample and haste until end of turn.

Whenever you scry, the next instant or sorcery spell you cast this turn costs {X} less to cast, where X is the number of cards looked at while scrying this way. +2: Draw a card, then scry 2. −3: Exile the top card of your library. Create a number of 1/1 blue Faerie Dragon creature tokens with flying equal to that card's mana value. Elminster can be your commander.

Experiment Kraj has all activated abilities of each other creature with a +1/+1 counter on it. {T}: Put a +1/+1 counter on target creature.