I would like to speculate what we can see next for the two other tiers my top guess would be ,
1. blast gun that clips on him
2.blast effect that plugs in hand Or gun if we get that too
3. Trask figure
4. A mega flight stand
5. A net catcher
I don’t count a second tentacle like others have because I think you can just get two sets and you will be able to put it on the figure to have two