I would hope this trick is not device dependent, but I guess I don't really know. I'll give you a hint. The trick here is similar to a trick that can instantly make a non-functioning teleporter, functional.
Yeah, I just figured this one out recently. It does ruin (potentially) a couple of my other levels...the ones where you have to melt the wrong doors before you trigger the right one. But dubble and trapple cross are the only ones I've designed like this. All the others I would suggest doing them honestly...they're more fun (and hard) that way. ;)
It's the same with the teleporter too. That trick can make any level using crystals obsolete.
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