The ongoing beef between Team Fortress 2's Reliable Excavation Demolition (RED) and Builders League United (BLU) teams isn't ending anytime soon.

Thankfully, with TF2's transformation into a free-to-play haven for lighthearted shooter action, more players than ever before can assume the distinct and hilarious personalities behind the game's nine classes.

But things have come a long way since the bitter-voiced Announcer's countdown of the first frag-filled round in 2007. Developer Valve's goal of mixing the fundamentals of TF2's gameplay (lifted from its predecessor Team Fortress Classic) with troves of content updates resulted in countless hours of replayability. Achievements, new maps and weapons, a cleanly executed shop interface, and yes, even bipolarizing hats all constituted a massively structured metagame that firmly entrenched players within the game's wonderfully campy 1960's spy flick visuals.

Read on for a brief look at how some of TF2's facets have significantly changed throughout the years.

Previous price: $19.99
Current price: Absolutely nothing

With the success of the in-game Mann Co. Store -- championed by the rugged Australian CEO character Saxton Hale -- furnishing players a range of methods for customizing their look and arsenal, the flexibility of a microtransactional business model easily trumped old-hat (no pun intended) MSRP. As a result, Valve nixed TF2's cost during the recent Uber content update. The population skyrocketed as a massive influx of new recruits surged into the servers, even handily unseating tactical shooter Counter-Strike's long-standing reign in total player count. Of course, veterans had a field day with the lovingly christened “free-2-players.”

Launch maps and modes: Six maps (Dustbowl, Granary, Gravel Pit, Well, 2Fort, Hydro) and three modes (Control Point, Capture the Flag, Territory Control)
Current maps and modes: Thirty-five maps and seven modes

TF2's original offering of maps and modes provided a suitable introduction to the presently used industrial motif, but players quickly demanded additional maps to shoot, blow up, and bludgeon their buddies in. Thanks to the rise in popularity of Valve's Hammer editing software, the number of battlegrounds ballooned in size and familiarized the community with fresh modes such as Payload --BLU escorts a bomb-laden rail cart down a winding track while RED desperately defends against an explosive doom.

Previous weapons and items: Three per class
Current weapons and items: Too many to count

Just one look at TF2's weapon list proves Valve's support of crowdsourced material for its games. Those with a knack for weapon design can submit their idea to Valve for consideration; if it meshes well within the game's heavily stylized world, it's thrown into the next content update. In fact, equipping certain sets of items gives an RPG-esque bonus to health, attack, or another stat. (For example, the Spy's Saharan set reduces the sound of his cloaking ability to barely a whisper.)

By contrast, the cosmetic hats offer no bonuses whatsoever and merely tweak the look of each class, but at least your secret desire to combine Dr. Suess with a rocket launcher can see the light of day.