diff --git a/src/go/engine.py b/src/go/engine.py
--- a/src/go/engine.py
+++ b/src/go/engine.py
@@ -8,7 +8,7 @@ from . import core
 # @param colorOut {BLACK,WHITE}: color to close the sequence
 def getTransitionSequence(state1,state2,colorIn,colorOut,diff):
 	eng.load(state1,diff)
-	eng.iterativelyDeepen(state2,colorIn,colorOut)
+	return eng.iterativelyDeepen(state2,colorIn,colorOut)
 
 
 class SpecGo(core.Go):
@@ -69,6 +69,7 @@ class Engine:
 			if seq:
 				seq.reverse()
 				return seq
+		return None
 
 	def dfs(self,state2,limit):
 		g=self._g
@@ -80,10 +81,6 @@ class Engine:
 			if m==PASS: # no reason for both players to pass
 				self._moveList[(1-g.toMove)>>1].remove(m)
 
-			if g.hash()==state2.hash():
-				self._undoMove(m,captured)
-				return [(g.toMove,*m)]
-
 			if limit>1:
 				seq=self.dfs(state2,limit-1)
 				if seq:
@@ -91,8 +88,12 @@ class Engine:
 					seq.append((g.toMove,*m))
 					return seq
 
+			if limit==1 and g.hash()==state2.hash():
+				self._undoMove(m,captured)
+				return [(g.toMove,*m)]
+
 			self._undoMove(m,captured)
-		return False
+		return None
 
 	def _undoMove(self,move,captured):
 		g=self._g