Deeler

The Deeler is a spider-like enemy appearing in The Adventure of Link.

Strategy
The Deeler attacks Link by dropping from the threads of spiderweb-like string. It can most easily be slain by inducing it to fall by running past and then hailing it with Sword Beams, but a sword slash will work as well. This enemy will stay concealed on the ceiling until Link, (or any non-monster traveler for that matter), comes wandering by. Once the unwary prey comes beneath it, the Deeler will let webs fall on the passer-by and then drop down to finish the victim. If Link is caught in a Deeler's webs, he must break out and slash the arachnid twice to kill it.

The blue variety of Deelers is stronger, and will drop down and attack from the ground.

Zelda's Adventure
Deelers in Zelda's Adventure come in two sizes, small and large. The smaller versions are fairly weak and can easily be defeated in a couple of hits, while the larger versions may take up to five hits from Zelda's Wand before going down. They no longer hang up in tree tops dropping down on webs to attack, instead opting to scurry around on the ground attempting to bump into Zelda.

Animated series
Two Deelers appear in the "Kiss'n Tell" episode of the animated series. After Ganon knocks Frog Link unconscious, he summons two Deelers to keep an eye on Link. As the Deelers get closer to the young hero, the young hero wakes up and eats the two spiders but is then disgusted by what he has done.

The Legend of Zelda comic
A Deeler briefly makes an appearance in the Missing in Action story of the Legend of Zelda comic. As Princess Zelda is riding away from Hyrule with her trusty horse Storm, a Deeler gets in the way of her path and scares Storm, causing Zelda to get knocked off into the ground.