At the end of Wind and Truth we see the potential of a new fused being made with the surge of adhesion. I'd love to hear other Ideas but here is mine first
The bound ones.
Appearance: tall imposing figures wrapped in chains made out of carapace that drag behind them in a clump. they are incredibly dull in color (dark blacks and dull reds) and incredibly dull of mind, however they are invincible.
Abilities: like stated above they are invincible as well as being very strong and dense, they are however very slow. they swing their chains around as a weapon because they cannot use their surge (yet). The radiants struggled with this threat until a windrunner found out that separating the chains around them from the clump dragging behind them made them vulnerable (kinda). When this happens The bound one grows more colorful (vivid oranges, reds, whites and blacks) gains control of their carapace chains (like limbs) gains access to their surge, gets smarter, lighter and faster. they now are, however, capable of dying. and in the bundle behind them is a weapon they used in their previous lives.
your turn.