Really? And if one stack dies, will the other one just keep mourning for its fallen comrade?

When one of the dendroids dies, the other one comes back to life.

So, what's the most interesting part that happens next?

Then this happens: the harpy flies away and is still under the effect of the binding spell. Even if the dendroid moves, the effect of the spell will not be lost. The harpy can only cast Protection! Even if the dendroid moves close and then moves away or dies, the effect of the binding will still remain. If the dendroid attacks itself, a new binding will be created, which will work normally.
P.S.: The Teleport spell removes the effect of the binding!
P.S.2: Below is a test drive, check it out if you're interested!
P.S.3: The most interesting thing is that this doesn't work in WoG anymore! They fixed it...

By the way, here are a few more notes about anti-magic.
It turns out that the expert dispel and the dragonfly are stronger.

In my opinion, the dragonfly doesn't dispel, but casts a spell of level 5 called "removal of good spells"!
Test: A magic mirror is placed on the golden dragon! The dragonfly attacks, and BANG! :D