The most expensive Thanos comic is Iron Man #55 (February 1973), the first appearance of the Mad Titan created by Jim Starlin: a CGC 9.8 copy sold for $13,025 on Comiclink. This is a Bronze Age comic — Thanos was born in 1973, well after the Silver Age. The keys that follow — Captain Marvel #25-28 (1973-74) and The Infinity Gauntlet #1 (1991) — form the essential spine of any collection dedicated to the Mad Titan.
Thanos is Jim Starlin's most enduring Marvel creation. Conceived during college psychology classes — the name references the Freudian concept of Thanatos, the death drive — he made his first appearance in The Invincible Iron Man #55 in February 1973, co-scripted by Mike Friedrich. As a Bronze Age character, there are no Thanos keys predating 1973: no Silver Age issue exists to track down. After an apparent death in 1977, he returned in 1990 in Silver Surfer #34 to set up the Infinity Gauntlet saga — the arc that became the narrative backbone of Avengers: Infinity War (2018, $2.05 billion worldwide) and Avengers: Endgame (2019, $2.79 billion worldwide), with Josh Brolin bringing the character to life in both films.
This guide sticks to the verifiable: eBay medians from our estimator (eBay.fr + eBay.com, June 2026) and records documented by specialist sources (Comiclink, Bleeding Cool, Heritage Auctions). A key reminder: eBay medians blend all grades and all printings — they reflect the entry-level market, not the value of high-grade CGC copies. The Captain Marvel (1968, 1st series) and The Infinity Gauntlet series are not covered by our estimator; figures cited for those titles come exclusively from documented web sources.
Thanos key issue ranking (real data, June 2026)
The eBay medians for Iron Man #55, Silver Surfer #34, and Avengers #125 are based on 54 to 73 listings each — a reliable signal for the entry-level market. The Infinity Gauntlet #1 and the Captain Marvel series fall outside the estimator's scope.
| Issue | Significance | eBay data (all grades) | Documented record |
|---|---|---|---|
| Iron Man #55 (Feb. 1973) | 1st appearance of Thanos and Drax the Destroyer | Median €9 · 73 listings | $13,025 (CGC 9.8, Comiclink) |
| Captain Marvel #25 (Mar. 1973) | Starlin's debut on the title — Thanos War begins | Series outside tool scope | Not publicly documented |
| Captain Marvel #28 (Sep. 1973) | Central key of the Thanos War arc (#25-33) | Series outside tool scope | Not publicly documented |
| Avengers #125 (1974) | Thanos in the main Marvel continuity | Median €9 · 54 listings | Not publicly documented |
| Silver Surfer #34 (Feb. 1990) | Thanos returns — prelude to the Infinity Gauntlet | Median €19 · 55 listings | Not publicly documented |
| The Infinity Gauntlet #1 (Jul. 1991) | Starlin/Perez — Thanos at the height of his power | Series outside tool scope | CGC 9.8: active copies on Heritage/eBay (prices vary) |
Record sources: Comiclink (via Bleeding Cool), Heritage Auctions, sellmycomicbooks.com, GoCollect.
Iron Man #55 (1973): the Mad Titan's Bronze Age debut
Published in February 1973, The Invincible Iron Man #55 contains the first appearance of Thanos — along with Drax the Destroyer, Starfox (Eros), Mentor, and Kronos. The story was conceived and drawn by Jim Starlin and co-scripted by Mike Friedrich; the cover is by Starlin and Joe Sinnott. This is a Bronze Age comic: no Thanos key predates 1973, and no Silver Age issue exists for this character.
Our eBay estimator returns a median of €9 across 73 listings — the strongest listing volume of any issue tested for this guide. That median reflects a blend of all printings and grades, dominated by ungraded or mid-grade copies. High-grade value lives in an entirely different bracket: a CGC 9.8 copy sold for $13,025 on Comiclink, a record documented by Bleeding Cool; a CGC 9.6 trades around $5,000 and a CGC 9.4 around $3,000 based on available market data. The book has corrected from its pandemic peak (2019–2021) but remains the most liquid Thanos key on the market.
Captain Marvel #25-28 (1973-74): the Thanos War by Starlin
When Jim Starlin took over Captain Marvel with issue #25 (March 1973), he transformed a struggling series into his cosmic laboratory. The arc known as the Thanos War runs from #25 to #33 and sees Thanos pursue the Cosmic Cubes to deify Death. Captain Marvel #28 (September 1973) is widely cited as the central key of this arc: it is one of the earliest Marvel stories to place Thanos as the main antagonist in a full-scale cosmic confrontation.
The Captain Marvel series (1968, 1st series) is not covered by our eBay estimator. These Bronze Age issues remain relatively accessible in ungraded condition, but their value in high-grade CGC is significantly higher. For collectors who want to explore this saga before investing in The Infinity Gauntlet, the Thanos Wars: Infinity Origin Omnibus (2019) collects the complete run of Captain Marvel #25-34.
Silver Surfer #34 (1990): Thanos returns
Published in February 1990, Silver Surfer vol.3 #34 marks Thanos's return to Marvel's main continuity — his first in-costume appearance since his apparent death in Marvel Two-in-One Annual #2 (1977). The story is by Jim Starlin, with art by Ron Lim and Tom Christopher. This issue is the opening chapter of the "Rebirth of Thanos" arc and the direct prelude to Thanos Quest (1990) and then The Infinity Gauntlet (1991).
Our estimator returns a median of €19 across 55 listings — a noticeable premium over the other Bronze Age issues tested here, reflecting stronger sustained demand for this modern-era key. As with all issues on this list, high-grade CGC copies command prices well above this entry-level median.
The Infinity Gauntlet #1 (1991): Thanos holds the universe in his hand
Published in July 1991, The Infinity Gauntlet is a six-issue limited series written by Jim Starlin and drawn by George Perez (#1-3) then Ron Lim (#4-6). Issue #1 sees Thanos — wielding all six Infinity Gems — fulfill Mistress Death's wish by erasing half of all life in the universe. That act — the Snap — is the narrative moment adapted directly in Avengers: Infinity War (2018). It is one of Marvel's most significant crossover events of the modern era.
The series is not covered by our eBay estimator. CGC 9.8 copies of The Infinity Gauntlet #1 circulate regularly on Heritage Auctions and eBay; their price varies depending on page quality and whether the copy carries a Starlin or Perez signature. In the absence of a single, publicly documented auction record, no reference figure can be cited honestly for this issue. It is a modern-era key that is accessible at entry and mid level, but whose CGC 9.8 white-pages copies reach significantly higher levels than the mass market.
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