Sonata Galaxia (Red)

This costs

less to play for each Runechant you control.

Search your deck for a Runeblade aura with cost X or less, put it into the arena, then shuffle.

If X is 2 or more, this gets go again.

Rulings

From the Heavy Hitters release notes

You choose the value of X when you play Sonata Galaxia.
The base cost of Sonata Galaxia is twice the value of X that you choose when it is played.
You do not gain an action point from go again of the Runeblade aura you put into the arena.
Choosing a Runeblade aura with cost less than X does not change the value of X for the remainder of the card.

Keyword notes

Go again - Go again allows multiple actions to be played in a turn when usually playing an action with use up your action point, and therefore end your turn. A card with go again gives the controller of that card or activated ability 1 action point when it resolves.

When an action with go again resolves, its controller gains 1 action point.
Multiple instances of go again on the same card or activated ability do not stack. If a card or activated ability has multiple instances of go again when it resolves its controller gains 1 action point only.
If an action with go again does not resolve, its controller does not gain 1 action point.
You cannot reveal a card with no to Belittle. The card must have a value to its power that is 3 or less. (0 is a value)