diff --git a/src/block/tile/TileFactory.php b/src/block/tile/TileFactory.php
index 515dd8c63..26e0af6a5 100644
--- a/src/block/tile/TileFactory.php
+++ b/src/block/tile/TileFactory.php
@@ -114,6 +114,13 @@ final class TileFactory{
 		$this->saveNames[$className] = reset($saveNames);
 	}
 
+	/**
+	 * @phpstan-param class-string<Tile> $class
+	 */
+	public function isRegistered(string $class) : bool{
+		return isset($this->saveNames[$class]);
+	}
+
 	/**
 	 * @internal
 	 * @throws SavedDataLoadingException
diff --git a/src/data/bedrock/block/convert/BlockObjectToStateSerializer.php b/src/data/bedrock/block/convert/BlockObjectToStateSerializer.php
index 367d38449..45784d409 100644
--- a/src/data/bedrock/block/convert/BlockObjectToStateSerializer.php
+++ b/src/data/bedrock/block/convert/BlockObjectToStateSerializer.php
@@ -225,6 +225,10 @@ final class BlockObjectToStateSerializer implements BlockStateSerializer{
 		return $this->cache[$stateId] ??= $this->serializeBlock(RuntimeBlockStateRegistry::getInstance()->fromStateId($stateId));
 	}
 
+	public function isRegistered(Block $block) : bool{
+		return isset($this->serializers[$block->getTypeId()]);
+	}
+
 	/**
 	 * @phpstan-template TBlockType of Block
 	 * @phpstan-param TBlockType $block
diff --git a/src/entity/EntityFactory.php b/src/entity/EntityFactory.php
index 03d9c03e6..970fd986f 100644
--- a/src/entity/EntityFactory.php
+++ b/src/entity/EntityFactory.php
@@ -219,6 +219,13 @@ final class EntityFactory{
 		$this->saveNames[$className] = reset($saveNames);
 	}
 
+	/**
+	 * @phpstan-param class-string<Entity> $class
+	 */
+	public function isRegistered(string $class) : bool{
+		return isset($this->saveNames[$class]);
+	}
+
 	/**
 	 * Creates an entity from data stored on a chunk.
 	 *
diff --git a/src/world/World.php b/src/world/World.php
index 3a7d0c538..afd01c628 100644
--- a/src/world/World.php
+++ b/src/world/World.php
@@ -2047,6 +2047,15 @@ class World implements ChunkManager{
 			throw new WorldException("Cannot set a block in un-generated terrain");
 		}
 
+		//TODO: this computes state ID twice (we do it again in writeStateToWorld()). Not great for performance :(
+		$stateId = $block->getStateId();
+		if(!$this->blockStateRegistry->hasStateId($stateId)){
+			throw new \LogicException("Block state ID not known to RuntimeBlockStateRegistry (probably not registered)");
+		}
+		if(!GlobalBlockStateHandlers::getSerializer()->isRegistered($block)){
+			throw new \LogicException("Block not registered with GlobalBlockStateHandlers serializer");
+		}
+
 		$this->timings->setBlock->startTiming();
 
 		$this->unlockChunk($chunkX, $chunkZ, null);
@@ -2769,6 +2778,11 @@ class World implements ChunkManager{
 				throw new AssumptionFailedError("Found two different entities sharing entity ID " . $entity->getId());
 			}
 		}
+		if(!EntityFactory::getInstance()->isRegistered($entity::class)){
+			//canSaveWithChunk is mutable, so that means it could be toggled after adding the entity and cause a crash
+			//later on. Better we just force all entities to have a save ID, even if it might not be needed.
+			throw new \LogicException("Entity " . $entity::class . " is not registered for a save ID in EntityFactory");
+		}
 		$pos = $entity->getPosition()->asVector3();
 		$this->entitiesByChunk[World::chunkHash($pos->getFloorX() >> Chunk::COORD_BIT_SIZE, $pos->getFloorZ() >> Chunk::COORD_BIT_SIZE)][$entity->getId()] = $entity;
 		$this->entityLastKnownPositions[$entity->getId()] = $pos;
@@ -2870,6 +2884,9 @@ class World implements ChunkManager{
 		if(!$this->isInWorld($pos->getFloorX(), $pos->getFloorY(), $pos->getFloorZ())){
 			throw new \InvalidArgumentException("Tile position is outside the world bounds");
 		}
+		if(!TileFactory::getInstance()->isRegistered($tile::class)){
+			throw new \LogicException("Tile " . $tile::class . " is not registered for a save ID in TileFactory");
+		}
 
 		$chunkX = $pos->getFloorX() >> Chunk::COORD_BIT_SIZE;
 		$chunkZ = $pos->getFloorZ() >> Chunk::COORD_BIT_SIZE;