While Battle Styles will include all the things that define the Sword & Shield TCG series, such as VMAX cards, the big new mechanic is, as the name suggest, battle styles
Once per turn, if a Dinosaur monster is Normal or Special Summoned (except during the Damage Step): You can Special Summon 1 "Jurraegg Token" (Dinosaur/EARTH/Level 1/ATK 0/DEF 0) to your opponent's field in Defense Position
Once per turn: You can Fusion Summon 1 "Melodious" Fusion Monster from your Extra Deck, using monsters you control as Fusion Materials, including this card
Feed the Swarm Feed the Swarm is about as clean as it gets and really drives home blacks mantra of greatness at any cost. It's enchantment removal that feels appropriately black, and doubling up as creature removal means its pretty safe to run without fear of never having a target
While on the field, you even get a draw whenever your opponent responds to your Lil-la or Ki-sikils effects