Top 10 Underrated Old-School Mecha Anime to Watch in 2025

The mecha genre has some heavy hitters like Mobile Suit Gundam and Neon Genesis Evangelion, but there are tons of awesome shows from the '90s and early 2000s that don’t get enough love. These hidden gems mix cool stories, unique mech designs, and themes that still hit hard in 2025, from deep psychological stuff to wild genre mashups. Perfect for streaming marathons, this list of 10 overlooked series dives into their worlds, characters, and what makes them special. Each one’s a must-watch for anyone hunting for fresh takes on giant robots.

1. The Vision of Escaflowne (1996)

This 26-episode gem follows Hitomi Kanzaki, a high school girl pulled into Gaea, a fantasy world where kingdoms battle with Guymelefs—mechs with a medieval, crystal-powered twist. Hitomi teams up with Van Fanel, Fanelia’s young king, who pilots the dragon-shifting Escaflowne against the Zaibach Empire. Directed by Kazuki Akane with a killer Yoko Kanno soundtrack, it blends isekai, romance, and mecha action, with Hitomi’s psychic visions shaping a story about fate and sacrifice. The Guymelefs, part organic, part machine, stand out from typical sci-fi bots, and the vivid animation brings Gaea’s war-torn beauty to life. Mixing shoujo heart, political drama, and epic battles, it’s a timeless adventure that’s still captivating for fantasy and mecha fans alike.

2. The Big O (1999)

Set in Paradigm City, where everyone’s got amnesia, this 26-episode noir-mecha mix follows Roger Smith, a slick negotiator who controls the giant megadeus Big O. Directed by Kazuyoshi Katayama, it feels like Batman meets giant robot fights. Roger, with his butler Norman and android R. Dorothy, digs into the city’s secrets while smashing mechanical foes. Big O’s chunky, retro design with piston-powered punches is a departure from sleek mechs, and the jazzy music amps up the moody atmosphere. Starting episodic, it grows into a deep dive on memory and identity, blending genres smoothly. Its Toonami run earned it a small fanbase, but its sharp style and big questions make it a great pick for fans of dark, thoughtful anime.

3. Giant Robo: The Animation (1992)

Also known as Giant Robo: The Day the Earth Stood Still

This 7-episode OVA, directed by Yasuhiro Imagawa, reworks a '60s manga into a steampunk epic. Daisaku Kusama, a kid with a wristwatch controller, commands the massive Giant Robo against the Big Fire group’s evil plans. The super robot, run by voice and gestures, dishes out retro-futuristic destruction, feeling like a tokusatsu hero. With Masamichi Amano’s epic orchestral score, the story mixes huge battles with loyalty, sacrifice, and heroism. Characters like the tragic Ginrei and villain Franken Von Vogler add heart to the action. Short but packed with high-quality animation, it’s a perfect watch for fans of intense action and emotional drama.

4. Gasaraki (1998)

Directed by Ryosuke Takahashi, this 25-episode series mixes gritty military action with mysticism. Yushiro Gowa, from the powerful Gowa family, pilots Tactical Armor mechs in a near-future Japan caught in global wars. The plot ties in corporate schemes, ancient Noh rituals, and creepy Kugai entities, with Yushiro’s psychic mech link adding a dark twist. The mechs focus on tactical, ground-based combat, keeping things precise rather than flashy, in line with Takahashi’s Votoms style. Its slow pace digs into war’s cost, cultural identity, and tech ethics, making it a brainy genre entry. Fans of Ghost in the Shell will dig its political depth and tense buildup, offering a smart watch that still feels relevant.

5. Martian Successor Nadesico (1996)

This 26-episode space opera, directed by Tatsuo Sato, tracks the Nadesico, a private warship with a messy crew fighting Jovian aliens. Akito Tenkawa, a reluctant mech pilot, deals with romance, trauma, and his obsession with anime, as the show pokes fun at mecha tropes through a fake series, Gekiganger 3. The Aestivalis mechs, with swappable parts for air, land, or space, deliver colorful battles, while the mix of comedy, drama, and sci-fi keeps things unpredictable. Yoko Kanno’s music adds emotional weight. Its clever humor and strong character arcs make it a fun yet touching watch, great for fans of self-aware stories like Ouran High School Host Club.

6. Brain Powerd (1998)

Yoshiyuki Tomino’s 26-episode series pits living Brain Powerd mechs against alien Orphans wrecking Earth. Teen Hime Utsumiya bonds with a sentient Brain Powerd, joining a resistance to save the planet. These organic mechs, grown not built, move with a creepy grace, unlike typical machines. The story tackles environmental ruin, family ties, and human evolution, with psychic pilot-mech bonds adding a personal touch to the chaos. Yoko Kanno’s dreamy score sets a surreal mood. Its abstract plot and green themes connect with today’s eco-conscious crowd, making this lesser-known Tomino work a unique pick for fans of his offbeat style.

7. Blue Gender (1999)

This 26-episode dystopian thriller follows Yuji Kaido, woken from cryosleep in 2031 to an Earth swarmed by insectoid Blue aliens. He joins a mech-piloting resistance with soldier Marlene, facing brutal survival. Directed by Masashi Abe, it features raw, low-tech mech fights—more like armored suits than giant robots—highlighting human vulnerability. Its intense violence and themes of despair, love, and redemption craft a heavy, emotional ride. The fight against extinction feels timely, making it a solid pick for fans of dark sci-fi like Berserk or Attack on Titan. Its gritty edge and smaller-scale mechs stand out from flashier shows.

8. Candidate for Goddess (2000)

Directed by Mitsuru Hongo, this 12-episode series (plus OVAs) follows Zero Enna, a teen training to pilot sentient Ingrids, humanoid mechs defending space colonies from alien Victims. Set in the Zion colony, it captures the tough life of young pilots, mixing coming-of-age drama with cosmic stakes. The Ingrids, with sleek, angelic looks, sync emotionally with pilots, making battles feel personal. Themes of sacrifice and teamwork drive the story, though an unfinished adaptation cuts it short. Its short runtime and focus on youthful drive make it an easy, heartfelt watch for fans of Top Gun-style training stories and clean mecha action.

9. Zone of the Enders: Dolores, i (2001)

Directed by Tetsuya Watanabe, this 26-episode series, tied to Hideo Kojima’s game, follows James Links, a freighter pilot who gets Dolores, an AI-driven Orbital Frame mech with a quirky personality. Their journey across the solar system mixes family drama—James reconnecting with his kids—with fast-paced mech battles. Dolores’ sentient nature and agile design steal the show, while the blend of humor, heart, and space opera feels like Firefly. Focusing on personal stakes in a galactic war, it’s a refreshing, character-focused watch for fans of emotional sci-fi with lively mechs.

10. Argento Soma (2000)

This 25-episode psychological drama, directed by Kazuyoshi Katayama, centers on Takuto Kaneshiro, a student broken by a lab accident involving alien tech. Drafted to pilot the bio-mech Frank against extraterrestrial threats, he wrestles with trauma and identity. The muted colors and grim tone, paired with Frank’s weird, organic design, create a chilling mood. It dives into redemption and revenge, echoing Evangelion but focusing tightly on personal grief. Its deep narrative and unusual mechs make it a great pick for fans of dark, introspective sci-fi.

These post-1990 mecha anime, often skipped for bigger names, show off the genre’s range—from fantasy adventures to noir mysteries and heavy thrillers. Their fresh designs, strong characters, and lasting themes make them awesome for rediscovery in 2025. Grab them on streaming sites or fan archives, and dive into these overlooked classics to spark your love for mecha’s golden era.