DG Dimension

When you would use this card, if you have a black Tamer in play, reduce the cost by 1.
[Main] [De-Digivolve 1] 3 of your opponent's Digimon. (Trash 1 card from the top of 3 of your opponent's Digimon. Stop trashing when you would trash a level 3 card or the Digimon's last card.) Then, delete 3 of your opponent's Digimon with play costs of 6 or less.
[Security] [Security] Activate this card's [Main] effect.