Become the Arknight (Blue)

Viserai Specialization

You may discard an action card. If you discard an attack action card this way, search your deck for a Runeblade non-attack action card, reveal it, and put it into your hand. If you discard a non-attack action card this way, search your deck for a Runeblade attack action card, reveal it, and put it into your hand. Shuffle. Go again

Rulings

From the Arcane Rising release notes

Discard a ‘non-attack’ action card. Search your deck for a Runeblade attack action card, reveal it, put it into your hand, then shuffle your deck.
Discard an attack action card. Search your deck for a Runeblade ‘non-attack’ action card, reveal it, put it into your hand, then shuffle your deck.
You choose the mode at the time you play the card.
Discarding the card happens on resolution of the of the card. If you cannot or choose not to discard a card, the effect will not resolve.
You may elect not to put a card into your hand. If you do, you still shuffle your deck.
You may not discard a non-action card, such as an instant.
You cannot discard more than one 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)