diff --git a/core/assets/baseparts/1605281306347.msch b/core/assets/baseparts/1605281306347.msch
index a200060661..1ef95d9ea5 100644
Binary files a/core/assets/baseparts/1605281306347.msch and b/core/assets/baseparts/1605281306347.msch differ
diff --git a/core/assets/baseparts/759638168080351252.msch b/core/assets/baseparts/759638168080351252.msch
deleted file mode 100644
index 7ebed705a8..0000000000
Binary files a/core/assets/baseparts/759638168080351252.msch and /dev/null differ
diff --git a/core/src/mindustry/ai/BaseAI.java b/core/src/mindustry/ai/BaseAI.java
index a4fb6404e9..7900b6608c 100644
--- a/core/src/mindustry/ai/BaseAI.java
+++ b/core/src/mindustry/ai/BaseAI.java
@@ -1,5 +1,7 @@
 package mindustry.ai;
 
+import arc.*;
+import arc.input.*;
 import arc.math.*;
 import arc.math.geom.*;
 import arc.struct.*;
@@ -17,16 +19,18 @@ import mindustry.world.*;
 import mindustry.world.blocks.defense.*;
 import mindustry.world.blocks.production.*;
 import mindustry.world.blocks.storage.*;
+import mindustry.world.blocks.storage.CoreBlock.*;
 
 import static mindustry.Vars.*;
 
 public class BaseAI{
     private static final Vec2 axis = new Vec2(), rotator = new Vec2();
     private static final float correctPercent = 0.5f;
-    private static final float step = 5;
     private static final int attempts = 4;
     private static final float emptyChance = 0.01f;
-    private static final int timerStep = 0, timerSpawn = 1;
+    private static final int timerStep = 0, timerSpawn = 1, timerRefreshPath = 2;
+    private static final int pathStep = 50;
+    private static final Seq<Tile> tmpTiles = new Seq<>();
 
     private static int correct = 0, incorrect = 0;
 
@@ -36,6 +40,13 @@ public class BaseAI{
     TeamData data;
     Interval timer = new Interval(4);
 
+    IntSet path = new IntSet();
+    IntSet calcPath = new IntSet();
+    @Nullable Tile calcTile;
+    boolean calculating, startedCalculating;
+    int calcCount = 0;
+    int totalCalcs = 0;
+
     public BaseAI(TeamData data){
         this.data = data;
     }
@@ -53,8 +64,76 @@ public class BaseAI{
             }
         }
 
+        //refresh path
+        if(!calculating && (timer.get(timerRefreshPath, 3f * Time.toMinutes) || !startedCalculating) && data.hasCore()){
+            calculating = true;
+            startedCalculating = true;
+            calcPath.clear();
+        }
+
+        //didn't find tile in time
+        if(calculating && calcCount >= world.width() * world.height()){
+            calculating = false;
+            calcCount = 0;
+            calcPath.clear();
+            totalCalcs ++;
+        }
+
+        //calculate path for units so schematics are not placed on it
+        if(calculating){
+            if(calcTile == null){
+                Vars.spawner.eachGroundSpawn((x, y) -> calcTile = world.tile(x, y));
+                if(calcTile == null){
+                    calculating = false;
+                }
+            }else{
+                var field = pathfinder.getField(state.rules.waveTeam, Pathfinder.costGround, Pathfinder.fieldCore);
+
+                int[][] weights = field.weights;
+                for(int i = 0; i < pathStep; i++){
+                    int minCost = Integer.MAX_VALUE;
+                    int cx = calcTile.x, cy = calcTile.y;
+                    boolean foundAny = false;
+                    for(Point2 p : Geometry.d4){
+                        int nx = cx + p.x, ny = cy + p.y;
+
+                        Tile other = world.tile(nx, ny);
+                        if(other != null && weights[nx][ny] < minCost && weights[nx][ny] != -1){
+                            minCost = weights[nx][ny];
+                            calcTile = other;
+                            foundAny = true;
+                        }
+                    }
+
+                    //didn't find anything, break out of loop, this will trigger a clear later
+                    if(!foundAny){
+                        calcCount = Integer.MAX_VALUE;
+                        break;
+                    }
+
+                    calcPath.add(calcTile.pos());
+
+                    //found the end.
+                    if(calcTile.build instanceof CoreBuild b && b.team == state.rules.defaultTeam){
+                        //clean up calculations and flush results
+                        calculating = false;
+                        calcCount = 0;
+                        path.clear();
+                        path.addAll(calcPath);
+                        calcPath.clear();
+                        calcTile = null;
+                        totalCalcs ++;
+
+                        break;
+                    }
+
+                    calcCount ++;
+                }
+            }
+        }
+
         //only schedule when there's something to build.
-        if(data.blocks.isEmpty() && timer.get(timerStep, Mathf.lerp(20f, 4f, data.team.rules().aiTier))){
+        if(totalCalcs > 0 && data.blocks.isEmpty() && timer.get(timerStep, Mathf.lerp(20f, 4f, data.team.rules().aiTier))){
             if(!triedWalls){
                 tryWalls();
                 triedWalls = true;
@@ -123,6 +202,13 @@ public class BaseAI{
             if(!Build.validPlace(tile.block, data.team, realX, realY, tile.rotation)){
                 return false;
             }
+            Tile wtile = world.tile(realX, realY);
+
+            //may intersect AI path
+            tmpTiles.clear();
+            if(tile.block.solid && wtile != null && wtile.getLinkedTilesAs(tile.block, tmpTiles).contains(t -> path.contains(t.pos()))){
+                return false;
+            }
         }
 
         //make sure at least X% of resource requirements are met
@@ -191,7 +277,8 @@ public class BaseAI{
                     }
                 }
 
-                if(any && Build.validPlace(wall, data.team, tile.x, tile.y, 0)){
+                tmpTiles.clear();
+                if(any && Build.validPlace(wall, data.team, tile.x, tile.y, 0) && !tile.getLinkedTilesAs(wall, tmpTiles).contains(t -> path.contains(t.pos()))){
                     data.blocks.add(new BlockPlan(tile.x, tile.y, (short)0, wall.id, null));
                 }
             }
diff --git a/core/src/mindustry/graphics/OverlayRenderer.java b/core/src/mindustry/graphics/OverlayRenderer.java
index 6723f81c66..6cc1a1a851 100644
--- a/core/src/mindustry/graphics/OverlayRenderer.java
+++ b/core/src/mindustry/graphics/OverlayRenderer.java
@@ -171,7 +171,7 @@ public class OverlayRenderer{
             Draw.reset();
 
             Building tile = world.buildWorld(v.x, v.y);
-            if(tile != null && tile.interactable(player.team()) && tile.acceptStack(player.unit().item(), player.unit().stack.amount, player.unit()) > 0 && player.within(tile, itemTransferRange)){
+            if(input.canDropItem() && tile != null && tile.interactable(player.team()) && tile.acceptStack(player.unit().item(), player.unit().stack.amount, player.unit()) > 0 && player.within(tile, itemTransferRange)){
                 Lines.stroke(3f, Pal.gray);
                 Lines.square(tile.x, tile.y, tile.block.size * tilesize / 2f + 3 + Mathf.absin(Time.time(), 5f, 1f));
                 Lines.stroke(1f, Pal.place);
diff --git a/core/src/mindustry/input/DesktopInput.java b/core/src/mindustry/input/DesktopInput.java
index 7771b30fed..b106abf168 100644
--- a/core/src/mindustry/input/DesktopInput.java
+++ b/core/src/mindustry/input/DesktopInput.java
@@ -484,7 +484,7 @@ public class DesktopInput extends InputHandler{
                 deleting = true;
             }else if(selected != null){
                 //only begin shooting if there's no cursor event
-                if(!tileTapped(selected.build) && !tryTapPlayer(Core.input.mouseWorld().x, Core.input.mouseWorld().y) && !player.unit().activelyBuilding() && !droppingItem &&
+                if(!tryTapPlayer(Core.input.mouseWorld().x, Core.input.mouseWorld().y) && !tileTapped(selected.build) && !player.unit().activelyBuilding() && !droppingItem &&
                     !tryBeginMine(selected) && player.unit().mineTile == null && !Core.scene.hasKeyboard()){
                     player.shooting = shouldShoot;
                 }
diff --git a/core/src/mindustry/input/InputHandler.java b/core/src/mindustry/input/InputHandler.java
index ed219c026e..c2ab8423c9 100644
--- a/core/src/mindustry/input/InputHandler.java
+++ b/core/src/mindustry/input/InputHandler.java
@@ -1056,6 +1056,10 @@ public abstract class InputHandler implements InputProcessor, GestureListener{
         return droppingItem;
     }
 
+    public boolean canDropItem(){
+        return droppingItem && !canTapPlayer(Core.input.mouseWorldX(), Core.input.mouseWorldY());
+    }
+
     public void tryDropItems(@Nullable Building tile, float x, float y){
         if(!droppingItem || player.unit().stack.amount <= 0 || canTapPlayer(x, y) || state.isPaused() ){
             droppingItem = false;
diff --git a/core/src/mindustry/maps/generators/BaseGenerator.java b/core/src/mindustry/maps/generators/BaseGenerator.java
index 5a1a72ad5e..8a5bf215ab 100644
--- a/core/src/mindustry/maps/generators/BaseGenerator.java
+++ b/core/src/mindustry/maps/generators/BaseGenerator.java
@@ -5,6 +5,7 @@ import arc.math.*;
 import arc.math.geom.*;
 import arc.struct.*;
 import arc.util.*;
+import mindustry.ai.*;
 import mindustry.ai.BaseRegistry.*;
 import mindustry.content.*;
 import mindustry.game.*;
@@ -146,6 +147,15 @@ public class BaseGenerator{
                 }
             });
         }
+
+        //clear path for ground units
+        for(Tile tile : cores){
+            Astar.pathfind(tile, spawn, t -> t.team() == state.rules.waveTeam && !t.within(tile, 25f * 8) ? 100000 : t.floor().hasSurface() ? 1 : 10, t -> !t.block().isStatic()).each(t -> {
+                if(t.team() == state.rules.waveTeam && !t.within(tile, 25f * 8)){
+                    t.setBlock(Blocks.air);
+                }
+            });
+        }
     }
 
     public void postGenerate(){
diff --git a/core/src/mindustry/ui/fragments/HintsFragment.java b/core/src/mindustry/ui/fragments/HintsFragment.java
index eb7d8ca854..1bc8ad6f1e 100644
--- a/core/src/mindustry/ui/fragments/HintsFragment.java
+++ b/core/src/mindustry/ui/fragments/HintsFragment.java
@@ -154,7 +154,7 @@ public class HintsFragment extends Fragment{
         respawn(visibleMobile, () -> !player.dead() && !player.unit().spawnedByCore, () -> !player.dead() && player.unit().spawnedByCore),
         launch(() -> isTutorial.get() && state.rules.sector.isCaptured(), () -> ui.planet.isShown()),
         schematicSelect(visibleDesktop, () -> ui.hints.placedBlocks.contains(Blocks.router), () -> Core.input.keyRelease(Binding.schematic_select) || Core.input.keyTap(Binding.pick)),
-        conveyorPathfind(() -> control.input.block == Blocks.titaniumConveyor, () -> Core.input.keyTap(Binding.diagonal_placement) || (mobile && Core.settings.getBool("swapdiagonal"))),
+        conveyorPathfind(() -> control.input.block == Blocks.titaniumConveyor, () -> Core.input.keyRelease(Binding.diagonal_placement) || (mobile && Core.settings.getBool("swapdiagonal"))),
         boost(visibleDesktop, () -> !player.dead() && player.unit().type.canBoost, () -> Core.input.keyDown(Binding.boost)),
         command(() -> state.rules.defaultTeam.data().units.size > 3 && !net.active(), () -> player.unit().isCommanding()),
         payloadPickup(() -> !player.unit().dead && player.unit() instanceof Payloadc p && p.payloads().isEmpty(), () -> player.unit() instanceof Payloadc p && p.payloads().any()),
diff --git a/core/src/mindustry/ui/fragments/PlacementFragment.java b/core/src/mindustry/ui/fragments/PlacementFragment.java
index 9115b16785..a42e1d6aa5 100644
--- a/core/src/mindustry/ui/fragments/PlacementFragment.java
+++ b/core/src/mindustry/ui/fragments/PlacementFragment.java
@@ -97,7 +97,7 @@ public class PlacementFragment extends Fragment{
     boolean gridUpdate(InputHandler input){
         scrollPositions.put(currentCategory, blockPane.getScrollY());
 
-        if(Core.input.keyDown(Binding.pick) && player.isBuilder()){ //mouse eyedropper select
+        if(Core.input.keyTap(Binding.pick) && player.isBuilder()){ //mouse eyedropper select
             Building tile = world.buildWorld(Core.input.mouseWorld().x, Core.input.mouseWorld().y);
             Block tryRecipe = tile == null ? null : tile.block instanceof ConstructBlock ? ((ConstructBuild)tile).cblock : tile.block;
             Object tryConfig = tile == null ? null : tile.config();
diff --git a/core/src/mindustry/world/blocks/campaign/Accelerator.java b/core/src/mindustry/world/blocks/campaign/Accelerator.java
index 419186fe56..9dd9040f8f 100644
--- a/core/src/mindustry/world/blocks/campaign/Accelerator.java
+++ b/core/src/mindustry/world/blocks/campaign/Accelerator.java
@@ -32,8 +32,10 @@ public class Accelerator extends Block{
 
     @Override
     public void init(){
+        itemCapacity = 0;
         for(ItemStack stack : launching.requirements){
             capacities[stack.item.id] = stack.amount;
+            itemCapacity += stack.amount;
         }
         consumes.items(launching.requirements);
         super.init();
diff --git a/core/src/mindustry/world/blocks/distribution/StackConveyor.java b/core/src/mindustry/world/blocks/distribution/StackConveyor.java
index 06d6f12068..b35f1630fb 100644
--- a/core/src/mindustry/world/blocks/distribution/StackConveyor.java
+++ b/core/src/mindustry/world/blocks/distribution/StackConveyor.java
@@ -106,6 +106,8 @@ public class StackConveyor extends Block implements Autotiler{
         public float cooldown;
         public Item lastItem;
 
+        boolean proxUpdating = false;
+
         @Override
         public void draw(){
             Draw.rect(regions[state], x, y, rotdeg());
@@ -168,15 +170,15 @@ public class StackConveyor extends Block implements Autotiler{
 
             //update other conveyor state when this conveyor's state changes
             if(state != lastState){
+                proxUpdating = true;
                 for(Building near : proximity){
-                    if(near instanceof StackConveyorBuild){
+                    if(!(near instanceof StackConveyorBuild b && b.proxUpdating && b.state != stateUnload)){
                         near.onProximityUpdate();
-                        for(Building other : near.proximity){
-                            if(!(other instanceof StackConveyorBuild)) other.onProximityUpdate();
-                        }
                     }
                 }
+                proxUpdating = false;
             }
+
         }
 
         @Override
diff --git a/core/src/mindustry/world/blocks/units/UnitFactory.java b/core/src/mindustry/world/blocks/units/UnitFactory.java
index 1a257d9565..6b2156e566 100644
--- a/core/src/mindustry/world/blocks/units/UnitFactory.java
+++ b/core/src/mindustry/world/blocks/units/UnitFactory.java
@@ -53,12 +53,15 @@ public class UnitFactory extends UnitBlock{
     @Override
     public void init(){
         capacities = new int[Vars.content.items().size];
+        itemCapacity = 0;
         for(UnitPlan plan : plans){
             for(ItemStack stack : plan.requirements){
                 capacities[stack.item.id] = Math.max(capacities[stack.item.id], stack.amount * 2);
-                itemCapacity = Math.max(itemCapacity, stack.amount * 2);
             }
         }
+        for(int i : capacities){
+            itemCapacity += i;
+        }
 
         super.init();
     }