diff --git a/src/main/kotlin/ru/dbotthepony/mc/otm/block/entity/cable/EnergyCableGraph.kt b/src/main/kotlin/ru/dbotthepony/mc/otm/block/entity/cable/EnergyCableGraph.kt
index f837fe360..3f0b335e6 100644
--- a/src/main/kotlin/ru/dbotthepony/mc/otm/block/entity/cable/EnergyCableGraph.kt
+++ b/src/main/kotlin/ru/dbotthepony/mc/otm/block/entity/cable/EnergyCableGraph.kt
@@ -1,5 +1,6 @@
 package ru.dbotthepony.mc.otm.block.entity.cable
 
+import it.unimi.dsi.fastutil.ints.IntRBTreeSet
 import it.unimi.dsi.fastutil.objects.Reference2ObjectOpenHashMap
 import it.unimi.dsi.fastutil.objects.ReferenceArraySet
 import it.unimi.dsi.fastutil.objects.ReferenceLinkedOpenHashSet
@@ -20,7 +21,6 @@ import ru.dbotthepony.mc.otm.graph.GraphNodeList
 import ru.dbotthepony.mc.otm.onceServer
 import java.util.*
 import java.util.concurrent.atomic.AtomicLong
-import kotlin.ConcurrentModificationException
 import kotlin.collections.ArrayList
 import kotlin.collections.HashSet
 import kotlin.collections.LinkedHashSet
@@ -85,9 +85,6 @@ class EnergyCableGraph : GraphNodeList<EnergyCableBlockEntity.Node, EnergyCableG
 			ContainsStatus.ABOUT_TO_BE_REMOVED, ContainsStatus.ABOUT_TO_BE_ADDED -> { } // do nothing
 			ContainsStatus.DOES_NOT_BELONG -> throw IllegalArgumentException("$node does not belong to $this")
 			ContainsStatus.CONTAINS -> {
-				if (isIteratingNodes)
-					throw ConcurrentModificationException("Bug trap: currently iterating energy receivers!")
-
 				for (dir in RelativeSide.entries) {
 					val pair = node to dir
 
@@ -594,9 +591,6 @@ class EnergyCableGraph : GraphNodeList<EnergyCableBlockEntity.Node, EnergyCableG
 	}
 
 	override fun onNodeRemoved(node: EnergyCableBlockEntity.Node) {
-		if (isIteratingNodes)
-			throw ConcurrentModificationException("Bug trap: currently iterating energy receivers!")
-
 		for (dir in RelativeSide.entries) {
 			val pair = node to dir
 
@@ -625,9 +619,6 @@ class EnergyCableGraph : GraphNodeList<EnergyCableBlockEntity.Node, EnergyCableG
 	}
 
 	override fun onNodeAdded(node: EnergyCableBlockEntity.Node) {
-		if (isIteratingNodes)
-			throw ConcurrentModificationException("Bug trap: currently iterating energy receivers!")
-
 		for (dir in RelativeSide.entries) {
 			val pair = node to dir
 			check(livelyNodes.add(pair))
@@ -637,19 +628,25 @@ class EnergyCableGraph : GraphNodeList<EnergyCableBlockEntity.Node, EnergyCableG
 		notifyThroughputsChanged()
 	}
 
-	private var isIteratingNodes = false
+	private val indicesToRemove = IntRBTreeSet()
+	private var recursionLevel = 0
 
 	fun receiveEnergy(howMuch: Decimal, simulate: Boolean, fromNode: EnergyCableBlockEntity.Node, fromSide: RelativeSide): Decimal {
-		livelyNodesList.shuffle(fromNode.blockEntity.level!!.otmRandom)
+		val thisLevel = ++recursionLevel
+		val isMaster = thisLevel == 1
 
+		if (isMaster)
+			livelyNodesList.shuffle(fromNode.blockEntity.level!!.otmRandom)
+
+		var i = -1
 		val itr = livelyNodesList.iterator()
 		var received = Decimal.ZERO
 		var residue = howMuch.coerceAtMost(fromNode.energyThroughput)
 		val snapshot = Reference2ObjectOpenHashMap<Segment, Decimal>()
 
-		isIteratingNodes = true
-
 		for (pair in itr) {
+			i++
+
 			// recursion prevention
 			if (!fromNode.currentlyTransferringTo.add(pair))
 				continue
@@ -659,8 +656,12 @@ class EnergyCableGraph : GraphNodeList<EnergyCableBlockEntity.Node, EnergyCableG
 				val side = node.sides[relSide]!!
 
 				if (!side.isEnabled) {
-					itr.remove()
-					check(livelyNodes.remove(pair)) { "Lively nodes Set does not contain $pair" }
+					if (isMaster)
+						itr.remove()
+					else
+						indicesToRemove.add(i)
+
+					livelyNodes.remove(pair)
 					continue
 				} else if (fromNode === node && side.side === fromSide) {
 					continue
@@ -669,8 +670,12 @@ class EnergyCableGraph : GraphNodeList<EnergyCableBlockEntity.Node, EnergyCableG
 				val it = side.neighbour.get()
 
 				if (it == null || it is EnergyCableBlockEntity.CableSide) {
-					itr.remove()
-					check(livelyNodes.remove(pair)) { "Lively nodes Set does not contain $pair" }
+					if (isMaster)
+						itr.remove()
+					else
+						indicesToRemove.add(i)
+
+					livelyNodes.remove(pair)
 					continue
 				}
 
@@ -751,7 +756,17 @@ class EnergyCableGraph : GraphNodeList<EnergyCableBlockEntity.Node, EnergyCableG
 			}
 		}
 
-		isIteratingNodes = false
+		recursionLevel--
+
+		if (isMaster && indicesToRemove.isNotEmpty()) {
+			val indices = indicesToRemove.iterator(indicesToRemove.lastInt())
+
+			while (indices.hasPrevious()) {
+				livelyNodesList.removeAt(indices.previousInt())
+			}
+
+			indicesToRemove.clear()
+		}
 
 		return received
 	}