Mardu Siegebreaker The first time I read this, I thought it could get your opponents creatures too, and this would make the card so much better
C Common Spellbook of Knowledge X SPELL Send to the GY either 1 Spellcaster monster you control, or 1 other "Spellbook" card from your hand or face-up field, except "Spellbook of Knowledge", and if you do, draw 2 cards
Case of the Locked Hothouse If ever there was a card that looked like someone just straight up designed it for Cube, Case of the Locked Hothouse is it
Each battle essentially has its own "life total" (like a Planeswalker): attack and damage it enough, and it will flip, transformed into a new card on your side of the table
Lower Text - Promo Info BOOSTER VS ROYAL KNIGHT [BT-13] CLOSECLOSE BT13-089 R Digimon Lv.6 Ravemon Color Purple Form Mega Attribute Vaccine Type Cyborg DP 12000 Cost 12 Digivolve Cost 1 4 from Lv.5 Digivolve Cost 2 - Upper Text [End of Your Turn] By deleting this Digimon that has a digivolution card with [Bird] or [Avian] in one of its traits, at the end of your opponent's turn, you may play 1 [Ravemon] from your trash without paying the cost