stuck at the part with the heart...
How are you stuck? Like it is too hard or is it a bug?
I don't know how to proceed! I want to bypass the spikes with the hand but there are always a few spikes up behind the first spikewall, even if I remove/replace the heart.
So are you talking about the hand spike puzzle or the first one? The first one you were just supposed to walk past as the zombie.