Stickytongue Sentinel

Reach
When Stickytongue Sentinel enters, return up to one other target permanent you control to its owner's hand.

Pond Prophet

Forest

Clifftop Lookout

Reach
When Clifftop Lookout enters, reveal cards from the top of your library until you reveal a land card. Put that card onto the battlefield tapped and the rest on the bottom of your library in a random order.

Long River Lurker

Ward {1}
Other Frogs you control have ward {1}.
When Long River Lurker enters, target creature you control can't be blocked this turn. Whenever that creature deals combat damage this turn, you may exile it. If you do, return it to the battlefield under its owner's control.

Mistbreath Elder

At the beginning of your upkeep, return another creature you control to its owner's hand. If you do, put a +1/+1 counter on Mistbreath Elder. Otherwise, you may return Mistbreath Elder to its owner's hand.

Valley Mightcaller

Trample
Whenever another Frog, Rabbit, Raccoon, or Squirrel you control enters, put a +1/+1 counter on Valley Mightcaller.

Three Tree Scribe

Whenever Three Tree Scribe or another creature you control leaves the battlefield without dying, put a +1/+1 counter on target creature you control.

Island

Splash Lasher

Offspring {1}{U} (You may pay an additional {1}{U} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
When this creature enters, tap up to one target creature and put a stun counter on it. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Dour Port-Mage

Whenever one or more other creatures you control leave the battlefield without dying, draw a card.
{1}{U}, {T}: Return another target creature you control to its owner's hand.

Treeguard Duo

When Treeguard Duo enters, until end of turn, target creature you control gains vigilance and gets +X/+X, where X is the number of creatures you control.

Sunshower Druid

When Sunshower Druid enters, put a +1/+1 counter on target creature and you gain 1 life.

Clement, the Worrywort

Vigilance
Whenever Clement, the Worrywort or another creature you control enters, return up to one target creature you control with lesser mana value to its owner's hand.
Frogs you control have "{T}: Add {G} or {U}. Spend this mana only to cast a creature spell."

Lilysplash Mentor

Reach
{1}{G}{U}: Exile another target creature you control, then return it to the battlefield under its owner's control with a +1/+1 counter on it. Activate only as a sorcery.