Rocket Pack

A Rocket Pack is the ammunition for the Rocket Launcher. Rocket packs are in all of the Unreal series games, only named differently. Usually, the packs contain 12 rockets, but the count can vary depending on the Rocket Launcher type and the game.

Unreal
The Rocket Launcher of Unreal, called the Eightball Launcher, uses cans of 12 Eightballs. Cans are animated - when you get close to them, their lids open and six bars land on the base. After that, the lid floats down and rests on the ring of bars. As one can provides 12 Eightballs, it's a very useful pickup. To get the full pack, you need to pick up 4 cans of Eightballs (not including Eightballs you get from the weapon pickup). It's a quite common item in the single player campaigns. Usually there are many cans of Eightballs before and after a boss fight, usually a form of a Titan. In the multiplayer map DmMorbias, Eightball cans are the only ammunition available.

Unreal: RTNP
Unreal - Return to Na Pali has the same Eightball cans as in Unreal, but as it adds a new type of a Rocket Launcher, there is additional ammunition for them. It is never officially named. In the code it is named simply as RLAmmo (Rocket Launcher Ammo), and when picked up, it simply says "You got 10 rockets". It is believed that the most precise name for it would simply be "Rocket Pack". As the Rocket Launcher of Return to Na Pali is very powerful, Rocket Packs are very useful. They are found in UMS drop boxes throughout the mission. They appear to be light-weight as the total ammo capacity of the Rocket Launcher is 100, so it takes even 10 Rocket Packs to fill the Rocket Launcher with ammo. As the rockets generally hit more than the Eightballs, Rocket Packs are as valuable as cans of Eightballs. Rocket Packs are found a lot less frequently.

Unreal 2
The ammo for the Shark, Rocket Launcher of Unreal 2, is called a Rocket Pack as well. They only contain 5 rockets, up to 40 maximum. Rocket Packs are very rare in the game and the main supply for rockets are Sharks, either dropped by enemies or as pickups. So the Rocket Packs are very useful, as rockets deal loads of damage and quite quickly use up ammo. You need 8 Rocket Packs to get the full backpack of rockets.

Unreal Tournament
The Rocket Launcher of Unreal Tournament uses Rocket Packs almost the same way cans of Eightballs are used in Unreal. Rocket Packs, however, no longer animate and are slimmer. They are a little more valuable, as rockets of Unreal Tournament deal somewhat more damage than Eightballs. They are very common in multiplayer maps, as they are fired quite rapidly, in a "spammy" way.

Unreal Tournament 2003
The Rocket Launcher of Unreal Tournament 2003 uses Rocket Packs as well. They are even more valuable, as the Rocket Launcher fires rockets extremely rapidly, and each Rocket Pack only gives 9 rockets, up to 30. That means you need more than 3 Rocket Packs to get the full inventory of rockets. They are common in maps, so they shouldn't cause too many problems.