Sunderflock

This spell costs {X} less to cast, where X is the greatest mana value among Elementals you control.
Flying
When this creature enters, if you cast it, return all non-Elemental creatures to their owners' hands.

Renewed Solidarity

As this enchantment enters, choose a creature type.
Creatures you control of the chosen type get +1/+0.
At the beginning of your end step, for each token you control of the chosen type that entered this turn, create a token that's a copy of it.

Twinflame Travelers

Flying
If a triggered ability of another Elemental you control triggers, it triggers an additional time.

Riveteers Ascendancy

Whenever you sacrifice a creature, you may return target creature card with lesser mana value from your graveyard to the battlefield tapped. Do this only once each turn.

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.