UndertakerG 10

Undertaker G10:
Pick up 3 tombstones without dying.

When you die, if you reach that point in the level again, you will see there is a tombstone with your Gamerpic on it. You can pick it up to refill a heart. You need to collect three of these in a row.

The difficulty in this is that the levels/stages are random at each layer, so guaranteeing a return to a spot you died is a little problematic.

Here is how I pulled this one off:

In the layer you're on, you want to aim to not collect the eyes needed to proceed. Once you have enough eyes, you will not return to a level/stage you died on. Continue to die early on in the various levels of the layer and don't collect your past tombstones if you see them. They won't disappear and you can actually have 2 or 3 on a level within a layer. Eventually, you will have a bunch saved up in the various levels of the layer. Collect these and you will be able to easily collect 3 without dying.

Having extra hearts when aiming to collect will also make this easier to complete without dying.

This achievement may be glitched in a way that benefits you. I didn't ever collect 3 consecutive tombstones throughout my entire time playing this game, I doubt I even managed to get 2. This unlocked for me after collecting my third tombstone, despite the fact that I had died in between them. If you don't enjoy this same luck, the best method is to find an old tombstone, DON'T collect it, and get killed somewhere in the vicinity of it. Repeat this once more, and you'll then have an area somewhere on a level where there are 3 tombstones close together. Then just continue playing as normal, and sooner or later, the needed area will spawn, and you'll have your chance to grab your 3 tombstones.