Scalestorm Summoner

Whenever this creature attacks, create a 3/1 red Dinosaur creature token if you control a creature with power 4 or greater.

Fendeep Summoner

{T}: Up to two target Swamps each become 3/5 Treefolk Warrior creatures in addition to their other types until end of turn.

Tivash, Gloom Summoner

Lifelink
At the beginning of your end step, if you gained life this turn, you may pay X life, where X is the amount of life you gained this turn. If you do, create an X/X black Demon creature token with flying.

Sphinx Summoner

Flying
When this creature enters, you may search your library for an artifact creature card, reveal it, put it into your hand. then shuffle.

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Yuna, Grand Summoner

Grand Summon — {T}: Add one mana of any color. When you next cast a creature spell this turn, that creature enters with two additional +1/+1 counters on it.
Whenever another permanent you control is put into a graveyard from the battlefield, if it had one or more counters on it, you may put that number of +1/+1 counters on target creature.

Bloodbat Summoner

Flying
At the beginning of combat on your turn, up to one target Blood token you control becomes a 2/2 black Bat creature with flying and haste in addition to its other types.

Voldaren Bloodcaster

Flying
Whenever this creature or another nontoken creature you control dies, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")
Whenever you create a Blood token, if you control five or more Blood tokens, transform this creature.

Voldaren Bloodcaster // Bloodbat Summoner

Fang-Druid Summoner

Reach
When this creature enters, you may search your library and/or graveyard for a creature card with no abilities, reveal it, and put it into your hand. If you search your library this way, shuffle.

Tilonalli's Summoner

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Whenever this creature attacks, you may pay {X}{R}. If you do, create X 1/1 red Elemental creature tokens that are tapped and attacking. At the beginning of the next end step, exile those tokens unless you have the city's blessing.

Scion Summoner

Devoid (This card has no color.)
When this creature enters, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this token: Add {C}." ({C} represents colorless mana.)

Trostani's Summoner

When this creature enters, create a 2/2 white Knight creature token with vigilance, a 3/3 green Centaur creature token, and a 4/4 green Rhino creature token with trample.

Rydia, Summoner of Mist

Landfall — Whenever a land you control enters, you may discard a card. If you do, draw a card.
Summon — {X}, {T}: Return target Saga card with mana value X from your graveyard to the battlefield with a finality counter on it. It gains haste until end of turn. Activate only as a sorcery.