Traveling Chocobo

You may look at the top card of your library any time.
You may play lands and cast Bird spells from the top of your library.
If a land or Bird you control entering the battlefield causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Bristly Bill, Spine Sower

Landfall — Whenever a land you control enters, put a +1/+1 counter on target creature.
{3}{G}{G}: Double the number of +1/+1 counters on each creature you control.

Brushfire Elemental

Haste
This creature can't be blocked by creatures with power 2 or less.
Landfall — Whenever a land you control enters, this creature gets +2/+2 until end of turn.

Sazh's Chocobo

Landfall — Whenever a land you control enters, put a +1/+1 counter on this creature.

Elvish Mystic

Mossborn Hydra

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
This creature enters with a +1/+1 counter on it.
Landfall — Whenever a land you control enters, double the number of +1/+1 counters on this creature.

Tannuk, Memorial Ensign

Landfall — Whenever a land you control enters, Tannuk deals 1 damage to each opponent. If this is the second time this ability has resolved this turn, draw a card.

Llanowar Elves

Collected Company

Look at the top six cards of your library. Put up to two creature cards with mana value 3 or less from among them onto the battlefield. Put the rest on the bottom of your library in any order.

Tifa Lockhart

Trample
Landfall — Whenever a land you control enters, double Tifa Lockhart's power until end of turn.