"Expensive" has three meanings in game dev. The answer changes per metric.
Star Citizen (Cloud Imperium Games) — $600M+ raised (Crowdfunding) since 2012. Still in Alpha (Persistent Universe + Squadron 42). Scope: Two games, 100+ star systems, FPS + Space Sim + Fidelity unmatched. Not released.
Grand Theft Auto V (Rockstar, 2013) — ~$265M Dev + ~$200–300M Marketing = ~$500M+ Total. Recouped Day 1 ($800M). Now $8.5B+ revenue.
Runner-up: Cyberpunk 2077 (~$174M Dev + ~$142M Marketing = ~$316M). Red Dead Redemption 2 (~$170–240M Dev + ~$200M Mkt = ~$400M).
Call of Duty: Modern Warfare 2 (2009) — ~$200M Marketing (incl. $50M "Red Box" TV spots, Jeep partnership, midnight launches). Dev ~$50M. Total ~$250M.
Modern contenders: Destiny 2 (~$140M Mkt), Star Wars: The Old Republic (~$200M+ Dev+Mkt).
| Metric | Winner | Amount |
|---|---|---|
| Dev Cost (Ongoing) | Star Citizen | $600M+ |
| Dev + Marketing (Released) | GTA V | ~$500M |
| Marketing Only | CoD: MW2 (2009) | ~$200M |
| Revenue (Game Sales) | Minecraft | 300M copies |
| Revenue (Lifetime Total) | GTA V / Fortnite | $8.5B / $20B+ |
| Single Copy (Auction) | Super Mario Bros. (NES) | $2M |