New Keyword: Cascade

[Skeggi]

Found this on MTGSalvation:

Keyword: 続唱 / 'Double Cast'

"[When you play this], Reveal cards from the top of your library until you reveal a nonland card with lesser converted mana cost than this spell. You may play that card without paying its mana cost. Then put all revealed cards still in your library on the bottom of your library [at random / in any order / --].Notes: This could trigger on playing the spell, or it could be a keyword action you simply enact like scry.

It appears on this not-yet-confirmed card:

Tar Shards
Instant (U)
'Double Cast'
~this~ deals 4 damage to target creature.
When you play this spell, reveal cards from the top of your library until you reveal a nonland card with lesser converted mana cost than this spell. You may play that card without paying its mana cost. Then put all revealed cards still in your library on the bottom of your library at random order.