Rampaging Baloths

Trample
Landfall — Whenever a land you control enters, create a 4/4 green Beast creature token.

Fleet Swallower

Whenever this creature attacks, target player mills half their library, rounded up.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Crocanura

Reach (This creature can block creatures with flying.)
Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)

Frogify

Enchant creature
Enchanted creature loses all abilities and is a blue Frog creature with base power and toughness 1/1. (It loses all other card types and creature types.)

Joint Exploration

Kicker {G} (You may pay an additional {G} as you cast this spell.)
Scry 2, then draw a card. If this spell was kicked, you may put a land card from your hand onto the battlefield.

Omnibian

{T}: Target creature becomes a Frog with base power and toughness 3/3 until end of turn.

Azusa, Lost but Seeking

You may play two additional lands on each of your turns.

Millikin

{T}, Mill a card: Add {C}. (To mill a card, put the top card of your library into your graveyard.)

Exploration

You may play an additional land on each of your turns.

Haze Frog

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, prevent all combat damage that other creatures would deal this turn.

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Crashing Drawbridge

Defender
{T}: Creatures you control gain haste until end of turn.

Cut Your Losses

Casualty 2 (As you cast this spell, you may sacrifice a creature with power 2 or greater. When you do, copy this spell and you may choose a new target for the copy.)
Target player mills half their library, rounded down.

Jade Avenger

Bushido 2 (Whenever this creature blocks or becomes blocked, it gets +2/+2 until end of turn.)

Spore Frog

Sacrifice this creature: Prevent all combat damage that would be dealt this turn.

Croaking Counterpart

Create a token that's a copy of target non-Frog creature, except it's a 1/1 green Frog.
Flashback {3}{G}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Archaeomancer

When this creature enters, return target instant or sorcery card from your graveyard to your hand.

Hedron Crab

Landfall — Whenever a land you control enters, target player mills three cards. (They put the top three cards of their library into their graveyard.)

Dryad of the Ilysian Grove

You may play an additional land on each of your turns.
Lands you control are every basic land type in addition to their other types.

Grolnok, the Omnivore

Whenever a Frog you control attacks, mill three cards.
Whenever a permanent card is put into your graveyard from your library, exile it with a croak counter on it.
You may play lands and cast spells from among cards you own in exile with croak counters on them.

Papercraft Decoy

When this creature leaves the battlefield, you may pay {2}. If you do, draw a card.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Ashaya, Soul of the Wild

Ashaya's power and toughness are each equal to the number of lands you control.
Nontoken creatures you control are Forest lands in addition to their other types. (They're still affected by summoning sickness.)

Froghemoth

Trample, haste
Whenever this creature deals combat damage to a player, exile up to that many target cards from their graveyard. Put a +1/+1 counter on this creature for each creature card exiled this way. You gain 1 life for each noncreature card exiled this way.

Forest

Plaxcaster Frogling

Graft 3 (This creature enters with three +1/+1 counters on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{2}: Target creature with a +1/+1 counter on it gains shroud until end of turn. (It can't be the target of spells or abilities.)

Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Eternal Witness

When this creature enters, you may return target card from your graveyard to your hand.