Where Are My Friends?

This achievement isn't necessarily hard, but it had me worried that I'd miss it when I was seeing no coins at all during all of these autoscrolling platformer sections. Luckily, I noticed a slight difference in the last auto scroller section.

Here's where the coins are:

So you swap back and forth between side scrolling and top down autoscrollers. The last one is backwards (you travel from right to left). After the water section, you will be jumping on platforms. You will see a bright green platform that looks more artificial. Make sure to jump onto this and hit down on the control stick as you come down (it's a warp pipe like in Super Mario Bros. You can't go down to the coins without hitting down). You will drop down to a hidden area with a bunch of coins. I didn't get them all the first time, but that's not a problem.

If you miss a coin, just make sure to die and then pick the rest up on a second or third run through this section. It took me two runs to get everything. I had about 5 coins left after my first run and the second one cleaned it up.