Shockwave tower block

core/src/mindustry/content/ErekirTechTree.java

@@ -161,7 +161,9 @@ public class ErekirTechTree{
                     node(regenProjector, () -> {
                         //TODO more tiers of build tower or "support" structures like overdrive projectors
                         node(buildTower, Seq.with(new OnSector(four)), () -> {
+                            node(shockwaveTower, () -> {
 
+                            });
                         });
                     });
                 });