Volcanic and Gas planets get items to increase passive attack bonus.
Icy's have Melters, Permafrost structures. Deserts and Barrens can be changed too.
We need something for Metallics!

Arc-Reactor: Space 2, Research 2, Attack 100.
Manipulates the magnetic fields to further science or unleash a powerful attack in defense of the planet.

High Density Metalworks: Space 2, Mining 1, Research 1 Defense 100
A workshop using dense metals and magnetic forces to construct rare alloys for study and use.

Other ideas?

Not to nit pick, but they do turn into Dysons.

Once.