Music and song aren’t the only things that make an opera. It takes costumes and set design, too. And the opera “Grendel” includes no shortage of visual effects to aid the tension between the familiar and the foreign, the good and the bad.

Costume designer Constance Hoffman and set designer George Tsypin worked closely with director Julie Taymor to develop costumes, puppets, and a massive set for the opus. “We all strongly felt that Grendel was contemporary, he had human qualities as well as beast aspects,” Ms. Hoffman said. “Grendel’s journey is about balancing or not balancing those two aspects of himself.”

Throughout the creative process, Ms. Taymor, Mr. Tsypin, and Ms. Hoffman exchanged ideas on how the libretto, co-written by Ms. Taymor and poet J.D.McClatchy, would be converted onto stage.

“The libretto starts with the idea of jumping off a cliff, then Grendel changes his mind, but he is always drawn by the idea of releasing into death,” Ms. Hoffman said. “Grendel talked a lot about a wall or cliff and is often seen looking at the world from heights as an outsider.”

And so, at the center of this work stands an imposing 48-foot-long, 28-foot-tall mechanical wall that is both physical and symbolic. It rises and falls, rotates around itself and is driven by two motors, computer programs, and four live operators from within.As the sole set piece, the wall creates the epic’s only scenery. With a Nordic winter’s ice cracking on one side and spring’s earth bursting forth on the other, the wall serves as unmistakable border line between the world of humans and the world of beasts, the world of us and the world of them.

As often in works by Ms.Taymor, who is best known for Broadway’s “The Lion King,” the visuals in “Grendel” tell a large part of the story. Not only the set, but also the costumes and puppetry are striking enough to be a show by themselves.

Human-scale puppets of flora and beasts are Grendel’s relatives. His many voices, constantly debating one another within him, walk the stage in form of shadows, or doppelgängers, who intone upon him in different scales. The chorus, the villagers, are a monochromatic and subtle mass of people who, unlike Grendel, lack individual identity.

The main colors used in this stark story are earthy shades of gray and brown. They strongly contrast the rich reds and greens of the dragon, sung by Denyce Graves, who plays a pivotal role to Grendel. Ms. Graves, backed by three singing dragonettes, is a fantastical figure who sees forward and backward. She finally entices Grendel to accept his role of intruder and wrong-doer from the other side.

Almost all the characters in “Grendel” wear costumes made of felt fabrics that strongly resemble medieval Nordic clothing. Even delicate Queen Wealtheow, sung by Laura Claycomb, will appear in a seemingly sheer white gown with long trailing train that is made of a combination of felt and finer fabrics. Ms. Graves’ dragon cape comes close to taking up the entirety of the stage.When combined with mask, tail, and fingernails that are a foot long, the costume creates a landscape all of its own. Grendel himself wears a heavy coat and old galoshes. His shadows haunt him as near identical triplets of a darker shaded gray.