Odin's Breath (BT13-106) - Versus Royal Knights

When an effect trashes this card from the security stack, activate this card's [Main] effect.
[Main] 1 of your opponent's Digimon gets -3000 DP until the end of your opponent's turn. Then, if there're 6 or fewer total cards in both players' security stacks, all of your opponent's Digimon gain [Security Attack -1] until the end of your opponent's turn.

[Security] Activate this card's [Main] effect.