The top right corner is the 'cost' that a player would need to spend to summon a Black Knight (two black mana from Swamps, in this case)
For good reason, its everything you could ever want in a Ninjutsu enabler
(2015-08-25) Gaining control of a creature doesnt cause you to gain control of any Auras or Equipment attached to it
Now, whenever you discard a creature card, you can pay three, six or nine mana to produce one, two or three copies of that same creature
By discarding 1 card from your hand, you can select 2 cards ("Charmer" monster, "Familiar-Possessed" monster, or "Possessed" Spell/Trap card) from your Deck, add 1 to your hand, and then Set the other to your field
If you're using cards that manage the chaos bag (Premonition or Dark Prophecy come to mind) then you have more control over whether or not the extra damage is triggered