Because Mojang didn't! (for some inconceivable reason)
Seeking Hearts gives inactive Creaking Hearts an analog comparator output when players look in its direction. When looking directly at the heart, it outputs a signal strength of 15. Other than that, the mod doesn't change its regular behavior; active hearts keep their vanilla comparator functionality.
Only needed on server to function. Client just puts the Creaking Heart in the Redstone tab.
Use it in all sorts of essential contraptions!
Pistons that gaslight you!
This really quite simple button!
And more!
Special thanks to Ocelot for helping get this finished at 3 AM