Remember the large Stomp&Chomp Grimlock toy for TF4, which was redecoed in green and sold as RID Grimlock?
Well, it had an interactive gimmick to co-sell with the 1-step toys for TF4, in which the feet of the 1-step toys had a magnet, that would activate a light and sound gimmick in the Stomp&Chomp Grimlock toy (when you stood them onto its back).

For TF5, it looks like the Mega 1-step Dragonstorm toy (a heavy remould of the Stomp&Chomp Grimlock toy), will have a similar line-wide gimmick with 1-step toys - a black light reveal of reactive paint decos.

And just like with TF4, the large toy (Dragonstorm) isn't scheduled for release until June-July, meaning that there could be three waves of 1-steps released before you can try out the bonus gimmick.

But you don't need the Dragonstorm toy this time to activate this line-wide gimmick... because if you have a black light torch, you can see the details already, and here are some photos to show what we are missing. (at the right angle, you can see the reactive paint on the surface of the toy, but the black light lights it up really nice)


(I'm not sure if black light, or UV lighting, is a good thing to be shining on your toys too often, as I would imagine that it is the component of sunlight that "sun damages" toys... which may not show up right away, but might change the colour or make them brittle in a few years time. Someone here correct me if this assumption is incorrect.)