msem-instigator

Flying, haste
Whenever Pyrus, the Undying Flame attacks, add {R}{R}{R}{R}. You don't lose this mana as steps, phases, and turns end.
{1}{R}: Pyrus gets +1/+0 until end of turn.

Qi-Long Shrine enters tapped.
{T}: Add {U} or {R}.
{U/R}, {T}, Sacrifice Qi-Long Shrine: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.

{T}: Add {C}.
{T}, Exile two cards from your graveyard: Add {G} or {U}.

{T}: Add {R} or {W}. You lose 1 life unless you have less life than an opponent.

Radiant Vistas enters tapped.
{T}: Add {W} or {U}.
{W}{U}, {T}, Sacrifice Radiant Vistas: Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Whenever you cast a noncreature spell, Rageborn Pyromancer gets +1/+1 until end of turn.
{1}{R}: Rageborn Pyromancer gets +1/+0 and gains flying until end of turn.

Raider's Den enters tapped.
{T}: Add {R}.
{R}, {T}: Target creature you control gains menace until end of turn. Activate only as a sorcery and only if you control a red creature.

({T}: Add {G} or {U}.)
Rainforest Spring enters tapped.

({T}: Add {W} or {U}.)
Rainsculpted Gorge enters tapped.
{1}, {T}: Add {W}{W} or {U}{U}.

Raintouched Basin enters tapped.
{T}: Add {U}.
Desertcycling {1}{U} ({1}{U}, Discard this card: Search your library for a Desert card, reveal it, and put it into your hand, then shuffle.)

Ralora, Unforgiving Depths enters tapped.
Whenever a source deals damage to you, put a creation counter on Ralora.
{T}, Remove ten creation counters from Ralora and sacrifice it: It deals 10 damage to target player or planeswalker.

({T}: Add {R} or {G}.)
Whenever Rampant Summit becomes tapped, you lose 1 life unless you control two or more basic lands.

Ravaged Monument enters tapped.
{T}: Add {G}.
{2/G}{2/G}: Ravaged Monument becomes a 4/4 green Elemental creature until end of turn. It's still a land.

Ravenous Hollow enters tapped.
{T}: Add {B} or {R}.
{2}{B}{R}: Until end of turn, Ravenous Hollow becomes a Wolf creature with first strike in addition to its other types.
Scavenge {2}{B}{R}

{T}: Add {C}.
{2}, {T}: Target creature gains haste until end of turn.

Flying

{T}: Add {C}.
{1}, {T}: Add one mana of any color. This ability costs {1} less to activate if there are three or more colors among cards in your graveyard.

As Reborn Altar enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {R}, {W}, or {B}.

Reclusive Copse enters tapped.
{T}: Add {B} or {G}.
{1}{B}{G}: Until end of turn, Reclusive Copse becomes an Insect creature with deathtouch in addition to its other types.
Scavenge {B}{G}

Whenever a creature dealt damage by Rei's Betrayer this turn dies, you gain life equal to that creature's toughness.

Rei, the Supplanter gets +1/+1 for each Forest you control.
At the beginning of each player's end step, if that player didn't play a land this turn, create a Forest token.

[+1]: Create a 1/1 blue Elemental creature token with flying, then crystallize twice. (Put a +1/+1 counter on a creature you control or create a Treasure.)
[–3]: Exile target nonland permanent. As long as it's exiled, its owner may pay {W}{U}{B}{R}{G} as a sorcery to put it into their hand.
[–7]: You get an emblem with “Pay 1 life: Add one mana of any color.” Then you gain 100 life.

Whenever a creature enters, each opponent loses 1 life.

{T}, Sacrifice Renewal Grove: Search your library for a basic land card, put it onto the battlefield, then shuffle. If Renewal Grove entered since your last upkeep, that land doesn't untap during your next untap step.

Whenever a creature dies, put a +1/+1 counter on Repository of Thoughts.
At the beginning of each combat, you may move a counter from Repository of Thoughts to target creature.