Where Scrap is intended to indicate a small structure or vehicle that has been destroyed and can easily be pulled apart and smelted down, Debris would indicate a large building or crashed starship that must be broken down into more manageable pieces. Debris act like destructible debris in StarCraft maps, blocking traversal and/or ramp access, but drop Scrap deposits when destroyed. The catch here is that these behemoths have the Scrap armor type, so are virtually indestructible until units that can break them apart can be produced. This both acts as a gating mechanism (certain map areas can be made inaccessible in the early game) and a “late game” store of resource value. I expect Debris (and the treasures hidden behind it) to become points of interest once Tier 2 units come onto the field.