Yeah.

src/main/java/WayofTime/bloodmagic/block/BlockInversionPillar.java

@@ -20,6 +20,7 @@ import WayofTime.bloodmagic.api.Constants;
 import WayofTime.bloodmagic.api.soul.EnumDemonWillType;
 import WayofTime.bloodmagic.block.base.BlockStringContainer;
 import WayofTime.bloodmagic.client.IVariantProvider;
+import WayofTime.bloodmagic.tile.TileAltar;
 import WayofTime.bloodmagic.tile.TileInversionPillar;
 
 public class BlockInversionPillar extends BlockStringContainer implements IVariantProvider
@@ -38,6 +39,19 @@ public class BlockInversionPillar extends BlockStringContainer implements IVaria
         setHarvestLevel("pickaxe", 2);
     }
 
+    @Override
+    public void breakBlock(World world, BlockPos blockPos, IBlockState blockState)
+    {
+        TileEntity tile = world.getTileEntity(blockPos);
+        if (tile instanceof TileInversionPillar)
+        {
+            TileInversionPillar tilePillar = (TileInversionPillar) world.getTileEntity(blockPos);
+            tilePillar.removePillarFromMap();
+        }
+
+        super.breakBlock(world, blockPos, blockState);
+    }
+
     @Override
     public boolean isOpaqueCube(IBlockState state)
     {

src/main/java/WayofTime/bloodmagic/inversion/InversionPillarHandler.java

@@ -13,7 +13,9 @@ import WayofTime.bloodmagic.tile.TileInversionPillar;
 
 public class InversionPillarHandler
 {
+    public static final double farthestDistanceSquared = 16 * 16;
     public static Map<Integer, Map<EnumDemonWillType, List<BlockPos>>> pillarMap = new HashMap<Integer, Map<EnumDemonWillType, List<BlockPos>>>();
+    public static Map<Integer, Map<EnumDemonWillType, Map<BlockPos, List<BlockPos>>>> nearPillarMap = new HashMap<Integer, Map<EnumDemonWillType, Map<BlockPos, List<BlockPos>>>>();
 
     public static boolean addPillarToMap(World world, EnumDemonWillType type, BlockPos pos)
     {
@@ -49,6 +51,61 @@ public class InversionPillarHandler
         }
     }
 
+    public static boolean removePillarFromMap(World world, EnumDemonWillType type, BlockPos pos)
+    {
+        int dim = world.provider.getDimension();
+        if (pillarMap.containsKey(dim))
+        {
+            Map<EnumDemonWillType, List<BlockPos>> willMap = pillarMap.get(dim);
+            if (willMap.containsKey(type))
+            {
+                if (willMap.get(type).contains(pos))
+                {
+                    return willMap.get(type).remove(pos);
+                } else
+                {
+                    return false;
+                }
+            } else
+            {
+                return false;
+            }
+        } else
+        {
+            return false;
+        }
+    }
+
+    private static void onPillarRemoved(World world, EnumDemonWillType type, BlockPos pos)
+    {
+        int dim = world.provider.getDimension();
+        if (nearPillarMap.containsKey(dim))
+        {
+            Map<EnumDemonWillType, Map<BlockPos, List<BlockPos>>> willMap = nearPillarMap.get(dim);
+            if (willMap.containsKey(type))
+            {
+                Map<BlockPos, List<BlockPos>> posMap = willMap.get(type);
+                List<BlockPos> posList = posMap.get(pos);
+                if (posList != null)
+                {
+                    Iterator<BlockPos> itr = posList.iterator();
+                    while (itr.hasNext())
+                    {
+                        BlockPos checkPos = itr.next();
+                        List<BlockPos> checkPosList = posMap.get(checkPos);
+                        if (checkPosList != null)
+                        {
+                            checkPosList.remove(pos);
+                        }
+                    }
+
+                    posMap.remove(pos);
+                }
+            }
+        }
+    }
+
+    //TODO: Change to use the nearPillarMap.
     public static List<BlockPos> getNearbyPillars(World world, EnumDemonWillType type, BlockPos pos)
     {
         int dim = world.provider.getDimension();

src/main/java/WayofTime/bloodmagic/item/block/ItemBlockInversionPillar.java

@@ -1,9 +1,15 @@
 package WayofTime.bloodmagic.item.block;
 
 import net.minecraft.block.Block;
+import net.minecraft.block.state.IBlockState;
+import net.minecraft.entity.player.EntityPlayer;
 import net.minecraft.item.ItemBlock;
 import net.minecraft.item.ItemStack;
+import net.minecraft.util.EnumFacing;
+import net.minecraft.util.math.BlockPos;
+import net.minecraft.world.World;
 import WayofTime.bloodmagic.block.BlockInversionPillar;
+import WayofTime.bloodmagic.registry.ModBlocks;
 
 public class ItemBlockInversionPillar extends ItemBlock
 {
@@ -13,6 +19,51 @@ public class ItemBlockInversionPillar extends ItemBlock
         setHasSubtypes(true);
     }
 
+    @Override
+    public boolean placeBlockAt(ItemStack stack, EntityPlayer player, World world, BlockPos pos, EnumFacing side, float hitX, float hitY, float hitZ, IBlockState newState)
+    {
+        if (!isBlockPillarBase(world.getBlockState(pos.offset(EnumFacing.DOWN)), newState) || !isBlockPillarCap(world.getBlockState(pos.offset(EnumFacing.UP)), newState))
+        {
+            return false;
+        }
+
+        return super.placeBlockAt(stack, player, world, pos, side, hitX, hitY, hitZ, newState);
+    }
+
+    public boolean isBlockPillarBase(IBlockState baseState, IBlockState newState)
+    {
+        Block block = baseState.getBlock();
+        if (block == ModBlocks.INVERSION_PILLAR_END)
+        {
+            int baseMeta = block.getMetaFromState(baseState);
+            int pillarMeta = newState.getBlock().getMetaFromState(newState);
+
+            if (pillarMeta == baseMeta / 2 && baseMeta % 2 == 0)
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    public boolean isBlockPillarCap(IBlockState capState, IBlockState newState)
+    {
+        Block block = capState.getBlock();
+        if (block == ModBlocks.INVERSION_PILLAR_END)
+        {
+            int capMeta = block.getMetaFromState(capState);
+            int pillarMeta = newState.getBlock().getMetaFromState(newState);
+
+            if (pillarMeta == capMeta / 2 && capMeta % 2 == 1)
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
     @Override
     public String getUnlocalizedName(ItemStack stack)
     {

src/main/java/WayofTime/bloodmagic/tile/TileInversionPillar.java

@@ -92,6 +92,11 @@ public class TileInversionPillar extends TileTicking
         }
     }
 
+    public void removePillarFromMap()
+    {
+
+    }
+
     public List<BlockPos> getNearbyPillarsExcludingThis()
     {
         return InversionPillarHandler.getNearbyPillars(worldObj, type, pos);