How many years did Black terrorize the future timeline before Future Trunks traveled back to get help?

[Angelus]

Did Zamasu just take his sweet time and play around with Mai's future resistance army? I just don't see how it took him so long to wipe out the humans on Earth.

Why did he even take his time when he already wiped killed all the Kaioshins of the 12 Universes of the future timeline, and presumably already accomplished his Zero humans plan across 11 of the said Future Universes. For fun?

[Jinzoningen MULE]

Bulma gathered fuel for one year before Trunks had enough to go back. We can assume she started no long after he had shown up.

Short Answer: A little over a year.

[Angelus]

It took him that long and Earth's human life wasn't wiped out yet? Black was either taking his sweet time because this may be the last planet on his multiversal conquest or he was waiting for Zamasu to arrive.

[Jinzoningen MULE]

It took him that long and Earth's human life wasn't wiped out yet? Black was either taking his sweet time because this may be the last planet on his multiversal conquest or he was waiting for Zamasu to arrive.

The anime implied that Black couldn't sense ki well in Goku's body until episode 47, so it makes sense.

[Boo Machine]

Well considering they would stop to have a tea party every now and then, we could assume they were just taking their time to admire their work and enjoy the scenery. Not in a huge hurry.

[Angelus]

The heck.. this would imply that Kaioshins don't know how to actually detect Ki? If such a prodigy like Zamasu can't detect Ki, how much more so that more ignorant Eastern Kaioshin. No wonder Eastern Kaioshin felt like shitting his pants by the sight of Pui Pui or Yakon. Dabura I can understand, but Pui Pui made Eastern Kaioshin scared?

[fadeddreams5]

The heck.. this would imply that Kaioshins don't know how to actually detect Ki? If such a prodigy like Zamasu can't detect Ki, how much more so that more ignorant Eastern Kaioshin. No wonder Eastern Kaioshin felt like shitting his pants by the sight of Pui Pui or Yakon. Dabura I can understand, but Pui Pui made Eastern Kaioshin scared?

Didn't Kibito sense SSJ2 Gohan's power? And they also sensed SSJ3 Goku from across the universe.

If Zamasu couldn't, it may be because he wasn't accustomed to his new body. That and convenience for the writers...

[Jinzoningen MULE]

If Zamasu couldn't, it may be because he wasn't accustomed to his new body.

That was my assumption.

[Angelus]

But Zamasu would have been in Black's body for a year.

Yeah but for some reason Kaioshin just can't seem to accurately gauge power.

[Kepiaschkz]

It's just because humans are too weaks for him to sense the Ki. And Trunks knows how to lower it to almost zero. Remember back in Buu Saga how Goku needed Trunks to pick up the Dragon Radar at his grandparents's house instead of just teleport to them ?

[thegamer23]

I always thought that was beacause Black couldn't feel human's KI in his early days.
Also, he didn't want to destroy the nature, wich he admired, so he couldn't just pull a death ball & get over it.

So it took time.