It has been 15 years since the MCU was born when Iron Man was released on May 2nd, 2008. Here is a list of the 15 best Marvel Movies in no particular order. MASSIVE SPOILERS.
Avengers: Endgame

Avengers: Endgame is the perfect conclusion. It has everything. It has a great story, it is bold, and it has an epic climatic battle. It is very distinctively broken up into 3 acts and a huge chunk of the movie is centered on story and character development. There are some actions scenes, but the action doesn’t really kick into gear until the final battle against Thanos’ (Josh Brolin) army. The intensity comes from the high stakes of losing half the universe including those who blipped out at the end of Infinity War. Endgame has one of the biggest casts with almost every major character appearing in the movie. There are multiple memorable moments including Captain America (Chris Evans) finally saying “Avengers, assemble” and Captain America being able to wield Mjolnir, Thor’s (Chris Hemsworth) hammer. The movie also said farewell to Captain America, Iron Man (Robert Downey Jr.), and Black Widow (Scarlett Johansson) with Iron Man sacrificing himself to stop Thanos once and for all and Black Widow also sacrificing herself to bring everybody back. This also clocks in at 3 hours and I would have been willing to sit through a 4 hour movie.
Avengers: Infinity War

Avengers: Infinity War was action packed throughout the whole movie. From the opening scene, the stakes were high, and the tone was set. Right off the bat, Thanos already has the Power Stone, and he kills Loki (Tom Hiddleston) who has the Space Stone. More major deaths occur throughout the film. This is also the movie that unites all the heroes with the Guardians of the Galaxy finally meeting the Avengers. The movie is full of epic moments and major surprises. It also is the first Marvel movie where the heroes lose. For the first time, Thanos succeeds in his plan to achieve the Infinity Stones so he can wipe out half of the universe.
Captain America: Civil War

Captain America: Civil War gives a taste of what was to come in Avengers: Infinity War and Avengers: Endgame when it comes to balancing a huge ensemble. Civil War is pretty much an Avengers movie to a degree. Half of the Avengers are in the movie. The only ones absent are Hulk (Mark Ruffalo) and Thor. Civil War balances a huge cast well and it still remains a Captain America movie even though Iron Man has a huge role. Civil War is the movie that tears the Avengers apart which leaves them separated when Infinity War happens. It also introduces audiences to Black Panther (Chadwick Boseman) and Spider-Man (Tom Holland). It has a massive showdown between Team Captain America and Team Iron Man pitting friends against each other.
Captain America: The Winter Soldier

Captain America: Winter Soldier is an intense thriller and is game changing to the MCU. It has one of the biggest twists in the MCU that has huge ramifications afterward with the reveal that Hydra is still around after all these years and it has infiltrated S.H.I.E.L.D. It also introduces Sharon Carter (Emily VanCamp) and Sam Wilson aka The Falcon (Anthony Mackie). It’s the first Captain America movie to be set in the present with the first movie set in the 40s. Captain America is both adjusting to life in the present as well as the fact that Bucky Barnes (Sebastian Stan) is actually alive, and he has been brainwashed and is now the Winter Soldier.
Spider-Man: No Way Home

Spider-Man: No Way Home is one of the best Marvel movies in Phase 4. It is a massive crossover event with Tobey Maguire and Andrew Garfield as their respective Spider-Men. All three team up together. It is heartwarming, funny, and an event. It is also game changing for the MCU’s Peter Parker. It blows the multiverse wide open.
Black Panther: Wakanda Forever

One of the best Phase 4 movies, Black Panther: Wakanda Forever has the difficult task of continuing without Chadwick Boseman who passed away in 2020 due to cancer. The movie is a beautiful film that pays tribute to King T’Challa and sees Shuri (Letitia Wright) take over the mantle as the Black Panther. It is action packed, heartfelt, and is an explosive conclusion to Phase 4 which also introduces Namor (Tenoch Huerta).
The Avengers

The Avengers is the conclusion to Phase 1 and does not disappoint. Out of 30 plus films, The Avengers is still one of the best and is the movie that reveals Thanos in the mid-credit scene which sets up the rest of the Infinity Saga.
Shang-Chi and the Legend of the Ten Rings

Shang-Chi and the Legend of the Ten Rings is a great introduction to Shang-Chi (Simu Liu). It has great action and is stunningly beautiful. It’s great as a solo movie and it has enough connections to the bigger universe.
Thor: Ragnorak

Thor: Ragnorak reinvigorates the Thor franchise. It is funny, action packed, and introduces great characters including Valkyrie (Tessa Thompson), The Grandmaster (Jeff Goldblum) and Korg (Taika Waititi).
Black Panther

Black Panther is the first and unfortunately only solo movie for T’Challa. It is a great introduction to the world of Wakanda. It has a great antagonist in Killmonger (Michael B. Jordan) and it has a great family dynamic between T’challa, Shuri, and Queen Ramonda (Angela Bassett). It also introduces the badass Dora Milaje which is led by Okoye (Danai Gurira).
Guardians of the Galaxy Vol. 3

Guardians of the Galaxy Vol. 3 is hauntingly beautiful, heartwarming, funny, and tragic. It is a stunning conclusion to the Guardians of the Galaxy trilogy and gives closure to all of the main characters. It also gives us a terrifying villain in The High Evolutionary (Chukwudi Iwuji) and finally gives us the debut of Adam Warlock (Will Poulter).
Guardians of the Galaxy Vol. 2

Guardians of the Galaxy Vol. 2 delves deeper into the characters and gives the audience a new look at Nebula (Karen Gillan). It has the same humor and is full of action and great character development especially between Nebula and Gamora (Zoe Saldana.)
Guardians of the Galaxy

Guardians of the Galaxy is a great introduction to a group of characters that many had not heard of at the time of its release. It is a fun and funny intergalactic space movie and has a great soundtrack. This is just the beginning of the wild ride the Guardians embark on.
Spider-Man: Far From Home

Spider-Man: Far From Home is a satisfying epilogue to Avengers: Endgame. The movie brings Nick Fury (Samuel L. Jackson) and Agent Hill (Cobie Smulders) in and has a great villain with Mysterio (Jake Gyllenhaal). The movie is action packed, full of twists, and sets up big things for the future.
Spider-Man: Homecoming

Spider-Man: Homecoming is the first Spider-Man movie in the MCU. It has everything Spidey fans could have asked for including villains who had not been in previous Spider-Man entrees.