As a free-to-play game, Marvel Heroes always has plans to sell more things. If you're obsessive enough to want almost every character and costume to come out in 2014, it will cost you about $130.
The official site lists two flavors of Advance Packs for 2014. The Advance Pack ($99) includes all 12 characters for the year, 36 Fortune Cards of different tiers, 12 Retcon Devices, and 12 Hero Stash Tabs. The Advance Pack Deluxe Edition ($129) doubles the Fortune Cards and Retcon devices, and includes one-month early access to Wolverine's "Fear Itself" costume and Gambit's "As Death" costume. Yeah, for a while there Gambit, the Cajun explodey mutant, became Death incarnate. Comics are weird.
The confirmed characters for the season include Dr. Strange, Juggernaut, Magneto, Moon Knight, Nightcrawler, Psylocke, Silver Surfer, Star-Lord, Sue Storm, and Venom. Two more characters will be included in the packs, but they're being kept under wraps for now. It's also worth pointing out that Nova is set for release in 2014 too, but he's not being included in the Advance Packs for the sake of those who already bought the Ultimate Founders Pack. Plus, do note the heroes are listed in alphabetical order, not necessarily the order of release.