How do I do temporary boosted movement in a platformer?

Hey everyone,

I've recently become obsessed with making cut-and-paste modules (XP systems, inventories, etc. etc.) and now I'm trying to do one that allows 'boosting' in a platformer. By that I mean having the character dash for a certain amount of time in a direction, just like in the old Rocket Knight Adventures game.

I've tried messing around with gravity angles, but it doesn't work cleanly, as restarting proper gravity just makes the character drop quickly instead of a decelerating drop. I imagined it would have to do with vectors, but I don't really understand how they work - if I put the vectorY to a few hundred he'll go up slowly, a few thousand and he flies through the roof. However with vectorX no matter what value I use he just moves a little bit.

Here's my capx if you want a look, but there's basically nothing in it, I just tried and deleted a bunch of ideas.

It's just simulate movement but with increased movement speed...

It's just simulate movement but with increased movement speed...

I don't see how that really works the same. You can't set the angle of movement, just simulate left/right, so you can't shoot down for example.

Currently the best I've got is with the bullet behaviour, which is equally as simple so I feel rightfully silly, just needed to add some deceleration after the boost period. Still there seems to be a few little issues, but generally it works as I wanted and I can tweak it easy enough from here.

Then it's resolved