Courier's Briefcase

Citizen

When this artifact enters, create a 1/1 green and white Citizen creature token.
{T}, Sacrifice this artifact: Add one mana of any color.
{W}{U}{B}{R}{G}, {T}, Sacrifice this artifact: Draw three cards.

District Guide

When this creature enters, you may search your library for a basic land card or Gate card, reveal it, put it into your hand, then shuffle.

Experiment One

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.)
Remove two +1/+1 counters from this creature: Regenerate it. (The next time this creature would be destroyed this turn, instead tap it, remove it from combat, and heal all damage on it.)

Gatebreaker Ram

This creature gets +1/+1 for each Gate you control.
As long as you control two or more Gates, this creature has vigilance and trample.

Gladecover Scout

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Gnarlback Rhino

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Whenever you cast a spell that targets this creature, draw a card.

Goreclaw, Terror of Qal Sisma

Creature spells you cast with power 4 or greater cost {2} less to cast.
Whenever Goreclaw attacks, each creature you control with power 4 or greater gets +1/+1 and gains trample until end of turn.

Hero of Leina Tower

Heroic — Whenever you cast a spell that targets this creature, you may pay {X}. If you do, put X +1/+1 counters on this creature.

Honored Hydra

Trample
Embalm {3}{G} ({3}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a white Zombie Snake Hydra with no mana cost. Embalm only as a sorcery.)

Imposing Sovereign

Creatures your opponents control enter tapped.

Hornet Nest

Insect

Defender (This creature can't attack.)
Whenever this creature is dealt damage, create that many 1/1 green Insect creature tokens with flying and deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Khalni Ambush

Target creature you control fights target creature you don't control. (Each deals damage equal to its power to the other.)

Khalni Territory

Khalni Ambush // Khalni Territory

Kraul Harpooner

Reach
Undergrowth — When this creature enters, choose up to one target creature you don't control with flying. This creature gets +X/+0 until end of turn, where X is the number of creature cards in your graveyard, then you may have this creature fight that creature.

Leafcrown Dryad

Bestow {3}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached.)
Reach
Enchanted creature gets +2/+2 and has reach.

Mistcutter Hydra

This spell can't be countered.
Haste, protection from blue
This creature enters with X +1/+1 counters on it.

Nemesis of Mortals

This spell costs {1} less to cast for each creature card in your graveyard.
{7}{G}{G}: Monstrosity 5. This ability costs {1} less to activate for each creature card in your graveyard. (If this creature isn't monstrous, put five +1/+1 counters on it and it becomes monstrous.)

Pioneer Masters