surging strikes booster box Pokémon Sparks while new ACE SPEC cards and more new Pokémon ex bring surprises of their own Surging Sparks (SV08) Booster Box

That means it can attack or block as soon as it hits the battlefield, but by your next upkeep it'll be turned off again

BT2-079 R Digimon Lv.6 VenomMyotismon Color Purple Cost 12 DP 12000 Digivolve Cost 1 Purple 4 from Lv.5 Form Mega Attribute Virus Type Dark Animal Card Text 1 [Effect] Security Attack +1 (This Digimon checks 1 additional security card.) [Opponent's Turn] When one of your opponent's Digimon becomes suspended, gain 1 memory

Many Supporter cards allow drawing three cards

Regardless of how effective the strategy may have been (I can't verify for myself personally), it's understandable that no one wants to lose a match like this so the card was just outright forbidden