1 Tuner + 1 or more non-Tuner monsters If you would take damage from a card effect, place 1 Black Feather Counter on this card instead. This card loses 700 ATK for each Black Feather Counter on it. Once per turn: You can remove all Black Feather Counters on this card, then target 1 face-up monster your opponent controls; that target loses 700 ATK for each Black Feather Counter you removed, and if it does, inflict damage to your opponent equal to the ATK lost by this effect.
Inflicts effect damage to your opponent equal to debuff.
Debuff effects needs to accumulate counters first which is slow.
Debuffs itself while negating effect damage.
Black-Winged Dragon will still negate effect damage and produce Black Feather Counters even when it's attack goes down to 0.
Take Effect Damage
Summon Lava Golem to remove monsters from your opponent's field and then take back your Lava Golem. Lava Golem will provide your Black-Winged Dragon with a continuous source of Black Feather Counters and Black-Winged Dragon will negate the effect damage from Lava Golem. Activate Burning Land to inflict 500 damage to your opponent every turn while your effect damage will be negated by Black-Winged Dragon and turned into Black Feather Counters to use against your opponent.
When you have gain a lot of counters use Reverse Trap to turn all those decreased attack into buffs that could easily put your Black-Winged Dragon as the strongest monster on the field. Do this while your opponent is attack to destroy their monster and possibly deal enough damage to win.