Trophy at [2640, 1390] on Founders Island...

[UncivilS3rvant]

Anyone know how to get this?

I follow the question marks using sonar up to the building just past Arkham Knights building.

The question marks go up the wall so I'm assuming I need to utilise the ramp to get up to the next accessible floor using the batmobile.

When I get across and re-start the sonar though, nothing happens.

And, of course, the longer you mess around the more chance the previous questions marks have of disappearing so you have to start again...

[JonoAMano]

Follow the question marks just past the ramp, then crab the car backward to the ramp while staying in Battle Scan mode and winch it up. Retrace your scan to the opposing building's highest point, then crab backward again while scanning -- don't slip out of Battle Scan mode until you're ready to jump the gap -- and inch forward to the top of the ramp until you see a new question mark pop atop your landing zone on the flat. Then reverse the car past the ramp and give it the full boosted beans to jump the gap.

After landing, start scanning again immediately. At upper left you'll see your final question marks pop and the target area.

[UncivilS3rvant]

A-ha...sneaky...

[bgray9054]

Ya, you basically have to be quick after jumping the ramp and switch into scanner mode as fast as possible. If you're too slow the question marks will start dwindling away. :)

[JonoAMano]

Exactly, good point about fadeaway. That's why it's important to stay in scan mode as long as possible, and to scan the uppermost visible question mark on the LZ before making the jump.