Thank you Tomek. Yeah, some have challenges have tricky objectives. For instance, I had a really hard time in one of the challenges that required using the remote controlled batarang. In BA: City and Origins, the controls for that gadget are quite different.

For combat challenges, it's easy to get a good score if instead of countering you attack more (since it counts as 2 for the combo instead of one) and if you do every combat takedown, stun and use both quick gadgets (claws and batarang) in every round. This will always give you +5000 points (variation bonus x9) but I think it only happen if your combo is not intterupted while you do this. You will also get 1000 points if your combo is not broken and 500 if you do not suffer any damage.

For predator challenges, don't worry about the time it takes. If you are having trouble try looking for videos on youtube. There are several that shows good ways to complete all objectives quite quickly.

Congratulations, good job.

Unfortunately I'm not that good to finish this game for 100%. All those challenges are just too hard for me.