That's pretty cool! I think we all did I wouldn't see why RobTop would just create the rotate trigger to rotate deco, enemies, and spikes. Also, someone asked him if he could add rotating slopes, and he said the programming wasn't the problem, it was only the blocks that would fit with the rotating slopes. So he probably came up with a solution to make a rotate trigger for that problem.
If I remember correctly, there was two different ways the rotation trigger worked: rotating like the editor button, and rotating the way you can achieve using move triggers. The first one will probably not work with the gameplay blocks, and the second one probably will.
I think robtop said somewhere before about an animation trigger which allows you to control the animation of objects like the dragons.
I have a quick theory on how the effects are happening. As you can tell in the sneak peek, the screen shakes and the icon can change colors. These are probably their own triggers, as the ground also shakes along with the ground. Regardless, these triggers are triggered by the touch/jump trigger. Remember the spawn trigger? That trigger was intended to activate a group/set of triggers once you activate it. The touch/jump trigger could have the same attributes; it will "spawn" (or activate) the triggers. Thus, explaining the ground shaking, everything flashing white, and the spider flashing white on the sneak peek, all of which happens when the player touches/jumps on an orb or uses the spider (which, obviously, is more than likely to require pressing the jump button) Also, I'm curious as to how the blue pad and the black orb interacts with the spider.
But I don't think it'd really make sense if it changed the icon for only those reasons. It'd be just easier to make a trigger for it, don't you think?
Well... Now that the wave and spider are duplicates of the ship and ball... time to wait for a new UFO duplicate gamemode. ( ͡° ͜ʖ ͡°)