Rune: Halls of Valhalla is a multiplayer-only expansion to the computer game Rune. It features many new characters to choose from, thirty three new maps, and most prominently: two completely new game modes.
New Game Modes
The first presents a gruesome parody of team sports, where players score points by beheading their opponents and throwing the severed heads into a goal. This style of play bears little resemblance to classic deathmatch, because players cannot gain points by killing their opponents--unless the head is cleanly removed, in which case it can be used as an extra 'ball'. However, while the mode was creative and original, many fans of the game were unable to find the same appeal that they did with classic deathmatch, and so its popularity was rather short lived.
The second new game mode, on the other hand, continues to be played on many servers today. The idea was to pit players against each other, 1 vs. 1, 2 vs. 2, or etc., in a closed, arena setting, resulting in what some would consider to be a true test of skill. Fans of the mode cite the fact that unlike in original deathmatch, players cannot rely on so-called 'cheap tactics' such as camping, respawn killing, ambushing, hitting-and-running, or avoid fights with skilled players to instead target the most vulnerable.
Unlike the creative and brutal HeadBall, this new mode was somewhat given in to by popular demand. Long before it was released, the same style still existed, except instead of enforcing a queue of players waiting to fight, it was based on the honor system instead. Newly arriving players would line up around an arena, and wait until the current fight was completed before rushing in. Players that did not follow the implied system of rules would be quickly derided by the rest, and it was not uncommon to ban repeat offenders. The fact that the idea of honor has a background in Norse culture led to the word being used occasionally to describe such a person's behaviour.
Changes to the Combat System
Besides new game modes, player models, maps, and revamped network settings reducing latency the combat system of the original game was drastically changed. Most prominently, the movement system in the original Rune, in which players move fastest when moving forward, slower when moving side to side, and slowest when moving backward, was changed so that the player moved equally quickly in all directions. One motivation behind this change was that the greater simplicity would improve gameplay performance over the internet. Due to more mobility for players, the result was faster-paced gameplay. However, this change was criticized by some Rune purists as being silly and unrealistic, for people should not move at the same speed forward and backward.
Weapon balance was also affected. Most notably, the use of Rune Powers, which grant the user magical abilities from their weapons, was tweaked so that it was usable. The expansion returned Power Runes as part of competitive gameplay, which in the original Rune, use of Power Runes was almost always forbidden due to fact that some rune powers were grossly overpowered. Besides Rune Powers, weapon damages for the goblin axe and work sword were toned down.
The collision system was modified so that weapons could block thrown weapons, which could not be done in the original game. This resulted in a dramatic decline in the viability of thrown weapons.
Effect on the Rune Community
Since the changes to the combat system were somewhat drastic, not all players were satisfied with the expansion. While a great number of competitive players moved to the expansion, some purists remained advocate to the original game, now commonly called "Rune 1.00" as opposed to "HOV". The original Rune game has maintained about 30% of all online Rune and HOV players over the years.
Later, Human Head Studios developed two new patches (1.06 and 1.07) in an attempt to address this incompatibility issue. Introducing a few bug fixes to both Rune Single Player and Multiplayer aspects. It also added the new "Rune Coop" GameType in the server menu. It also changed the original Rune Multiplayer combat mode to Rune Halls of Valhalla's own style while leaving the Single Player alone.
A note: Rune Halls of Valhalla Multiplayers can not play the Rune Coop Teamplay developed by a Runegame community's "Coop Team" (with help from Human Head Studios) first released in June 2001 (with a later Rune Co-op v1.2 version in December 21, 2001) Based on the original Single Player game, many levels were altered for cooperative play with some new ones included. Unless Rune Halls of Valhalla players had a few specific files found only in the Single Player, this particular mod is closed to them.
Although the patches allowed Rune Multiplayers to enter "HOV" Multiplayer servers in Deathmatch games. Arena and Headball were closed to them. They have allowed them to play certain HOV mods and DM maps made only for it. However, sadly, these also prevented them from reentering Rune 1.00 multiplayer servers because of the above described drastic changes. Only by renaming the Rune 1.06/1.07 folder and then reinstalling Rune 1.00 could they return. The later 2001 release of "Rune Gold" (which had both Rune and Rune Halls of Valhalla) came with Rune Multiplayer already patched to 1.06 with no alternative to enter Rune 1.00 Multiplayer servers. Outside of Rune Coop servers, there only a few Rune 1.06/1.07 multiplayer servers are ever put up.
Yet, the compromise was, more or less, successful considering its intended purpose.
On September 9, 2005, a community made "1.08 Patch" was released that finally allowed "Redirected Downloads to Rune Halls of Valhalla multiplayers (But not for Rune 1.00) Although not made by Human Head Studios, they did help the team and gave them  full authorization and endorsement.
Made for the expansion pack only, the 1.08 patch fixed some previous multiplayer and server problems while still allowing 1.06/1.07 clients to join 1.08 servers. (It also allowed the reverse to happen) It provided an in-game "News" tab that redirected to Runehordes.info where active admins (US and EU) updated that page. The patch also included the popular "Capture the Torch (CTT) gameplay mode with new maps. Several new Arena and Deathmatch maps where also included. Importantly though, amongst the new added features was a "Retro Movement" to customize RuneHOV Multiplayer servers to play "like Rune 1.00" that some wanted.
So finally with the 1.08 patch, those who only had the Rune Halls of Valhalla Multiplayer Expansion Pack (or Rune Gold) could play the original Rune 1.00 Multiplayer movements with the server customization. Yet, unless the original Rune 1.00 Multiplayer was patched with all three, they are still unable to join or the reverse to happen. The changes are still too drastic.
The Rune multiplayer community is still active, with clans, guilds, and players from around the world. Info on Rune clans can be found at Rune Hordes - though the site is now closed since August 2008, and while it is still online, is no longer getting updated.