msem-instigator

({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.)

Return up to one target creature card with mana value 1 or less from your graveyard to the battlefield.

Art of war — At the beginning of your end step, if Raiun Bay Junk dealt damage to an opponent this turn, put a +1/+1 counter on it.
Tap an untapped creature you control: Raiun Bay Junk becomes an artifact creature until end of turn.

Equipped creature gets +1/+1 for each Equipment attached to it.
Whenever an Equipment you control enters, attach it to equipped creature.
Equip {2}

Equipped creature has “Whenever this creature attacks, untap each other creature you control.”
Equip {3}

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.

Defender, reach
Bulwark — {X}, {T}: Rampart Ballista deals X damage to each opponent. X can't be greater than the number of creatures you control with toughness 4 or greater.

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.

Equipped creature is a Flagbearer in addition to its other types.
While an opponent is choosing targets as part of casting a spell they control or activating an ability they control, that player must choose at least one Flagbearer on the battlefield if able.
Equip {5}

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}

You may return a land you control to its owner's hand rather than pay this spell's mana cost.
Rawthlin Market Line enters tapped.
{T}: Add {G}.

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

{T}: Add {C}.
{T}, Reappropriate: Add one mana of any color. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)

{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}

Menace
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Vehicle becomes an artifact creature until end of turn.)

When Recon Drone enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle. Then if you did, put a card from your hand on the bottom of your library.

Flash
{1}, {T}: Scry 1.

Whenever you draw a card, put a hatch counter on Reefcrown Egg.
{T}, Sacrifice Reefcrown Egg: You may put a creature card with mana value less than or equal to the number of hatch counters on Reefcrown Egg from your hand onto the battlefield.
Cycling {2} ({2}, Discard this card: Draw a card.)

Put up to one target permanent card from your graveyard on top of your library. (Then exile this card. You may play the land later from exile.)

[+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.