The 7 best post-credits scenes in the Marvel Cinematic Universe, ranked

Thanos first appeared in the after-credits scene of "The Avengers" and again in "Guardians of the Galaxy," where he had actual lines of dialogue. But while 2015's "Age of Ultron" may be a disappointing movie, Thanos' brief appearance in the after-credits scene of the movie sets him up for a fight with the Avengers that we finally got in "Infinity War" this year. After the Avengers defeat Ultron, Thanos takes the Infinity Gauntlet and vows "I'll do it myself," setting him on an eventual collision course with Earth's Mightiest Heroes.

Another disappointing movie with a memorable post-credits scene, "Iron Man 2" (2010) teases the arrival of Thor. The scene features Agent Coulson driving up to a crater in a New Mexico desert. The crater is from Thor's hammer crash-landing to Earth after Odin banished Thor and put a spell on his hammer, as seen the following year in "Thor."

"Ant-Man and the Wasp" may have just come to theaters, but it features a great mid-credits scene that benefits from the excitement — and shock — of "Infinity War." In the scene, Hank and Janet Pym and Hope (a.k.a. Wasp) send Scott (Ant-Man) into the Quantum Realm. But while he's in there, the three on the outside disappear from Thanos' snap seen in "Infinity War." Scott is left stranded in the Quantum Realm, and we'll have to wait until the next "Avengers" movie to see his fate.

During last year's "Spider-Man: Homecoming," the movie's villain, the Vulture, realizes Spider-Man's secret identity. But when he is sent to prison by the end of the movie, he refuses to reveal that Spider-Man is Peter Parker when another inmate asks him during the after-credits scene. Michael Keaton is reportedly reprising his role in next year's sequel, "Far From Home," so we'll see if this has any further ramifications for the web-slinging superhero.

This one isn't exactly "important" to the overall story but it's Baby Groot dancing to "I Want You Back" by the Jackson 5, so how can you not love it?

The finale of "Infinity War" is already devastating, as Thanos achieves his goal and wipes out half of humanity, including many of our favorite characters. The post-credits scene piled on the hurt when Nick Fury vanishes from the Thanos snap — but not before he makes a call to Captain Marvel, who Brie Larson is playing in a standalone movie in March.

The original post-credits scene is still the best. Tony Stark, who's just revealed that he's Iron Man to the world, is approached by Nick Fury about an "Avenger Initiative." And the rest is history.