I needed to pass the time.

[Muninn]

I'd have two powers, controlling time and nullifying the power of any annoying super who hassled me.

Random hero - Stop Jack, your nefarious schemes will proceed no more!
Me - Oops, you don't exist anymore.
Random hero - Wha!? I'm disappearing into nothingness!
Me - I used my powers to go back in time and cause your mother to have a miscarriage, farewell.

[The MAZZTer]

I'd have two powers, controlling time and nullifying the power of any annoying super who hassled me.

Random hero - Stop Jack, your nefarious schemes will proceed no more!
Me - Oops, you don't exist anymore.
Random hero - Wha!? I'm disappearing into nothingness!
Me - I used my powers to go back in time and cause your mother to have a miscarriage, farewell.

But then some other random hero (or that hero, before he disappears completely) would go back in time to stop you before you could perform the dastardly deed! And they would succeed. At least, that's what always happens on the Sci-Fi channel...

[VenM2]

I'd have two powers, controlling time and nullifying the power of any annoying super who hassled me.

Random hero - Stop Jack, your nefarious schemes will proceed no more!
Me - Oops, you don't exist anymore.
Random hero - Wha!? I'm disappearing into nothingness!
Me - I used my powers to go back in time and cause your mother to have a miscarriage, farewell.

Never fear! For the Doctor will fix everything!

[nickspoon]

I am an evil genius philanthropist.

I once used my doomsday device to destroy an oppressive dictator and then spread his wealth amongst all the starving families of the country. They now live in peaceful, thriving democracy. BWAHAHAHAHAHA.

[Muninn]

I'd have two powers, controlling time and nullifying the power of any annoying super who hassled me.

Random hero - Stop Jack, your nefarious schemes will proceed no more!
Me - Oops, you don't exist anymore.
Random hero - Wha!? I'm disappearing into nothingness!
Me - I used my powers to go back in time and cause your mother to have a miscarriage, farewell.

But then some other random hero (or that hero, before he disappears completely) would go back in time to stop you before you could perform the dastardly deed! And they would succeed. At least, that's what always happens on the Sci-Fi channel...

The hero would need to have time powers too. And I would sort him/her out beforehand.

[Tom Flapwell]

"Beforehand" could be tricky with racing time travelers.