Once with its own attack, and then again by giving a huge bonus to another creature
It appears as though Wizards of the Coast did not want to risk the set not selling packs due to mediocre new cards, so they loaded Conspiracy with a bunch of high-quality reprints and a couple of juicy Eternal plants
Who thought this had anything to do in a madness strategy
I do think that's a concern, and I share it, but I think it's the wrong way to think about it
They are treated as having the same Type, Attribute, Level, ATK and DEF as regular versions of the cards
During the opponents turn, Gumblar will discard another 2 cards, while Borreload Savage Dragon or Hot Red Dragon Archfiend Abyss would negate the last card, leaving the opponent with no plays