It wont copy other effects that have changed the targeted creatures power, toughness, types, color, or so on
Instead of stealing guys you kill them and gain life, you still blow up planeswalkers and instead of blowing up lands you make 3/3s so you always have stuff to do
The idea here is to attack and give a defender suspected so it cannot block and get your swing in and if you had haste you could do that twice and stop two blockers
Black Widow, Intel Expert is quite an interesting card
Even though there are just under a dozen options, the Legendary Hydras that you can choose from each have abilities that make them a solid option, whether that's Haste, Trample, or a special activated ability
Potentially drawing removal and combat damage out of your opponents is just a bonus