Beast of Burden (often abbreviated to BoB) is a type of Summoning familiar that has the ability to carry items for the player. To access their familiar's inventory, players need only to click on them, or interact with them and manually ask them to open their inventory. The familiars with this ability are shown in the table below.

List of Beasts of Burden

Standard

	Familiar		Slots	Time (min)
13		Thorny snail	3	16
14		Spirit pack pig (Tier 1)	4	17
25		Spirit kalphite	6	22
40		Bull ant	9	30
44		Spirit pack pig (Tier 2)	8	35
52		Spirit terrorbird	12	36
67		War tortoise	18	43
84		Spirit pack pig (Tier 3)	22	55
96		Pack yak	30	58
99		Pack mammoth	32	64

Rune essence

	Familiar		Slots	Time (min)
54		Abyssal parasite	7 Essence	30
62		Abyssal lurker	12 Essence	41
93		Abyssal titan	20 Essence	42

Divine memories

	Familiar		Slots	Time (min)
81		Nightmare muspah	32 memories	60

Item storage

If players have a Beast of Burden (BoB) familiar with them with the bank window open, they can deposit its entire inventory into their bank by clicking the summoning familiar icon at the bottom of the bank interface, similar to the 1-button inventory or equipped items deposit feature. Players can also Withdraw-X from a bank to BoB without having to exit the bank or use bank presets to automatically withdraw items to a Beast of Burden.

There is also a give-all option, which would deposit all inventory items, prioritized according to their order in the inventory, into the familiar's inventory. However, this option is not available in the summoning interface and only shows up on the familiar's interface, so it is not possible to do in combat.

Before the familiar's time limit is up, two messages will appear, along with a tick-tock sound:

• You have 1 minute before your familiar vanishes.
• You have 30 seconds before your familiar vanishes.

After that: Your familiar has dropped all the items it was holding. You will have exactly five minutes until your items disappear for you to pick them up, which is significantly longer than if you had dropped them yourself. This technique is useful in fighting difficult bosses.

Limits of items carried

Currently, the known limits for what a beast of burden will carry are as such:

• Most Tradeable items can be stored if the value of each stack is less than a certain amount that varies by familiar. The exceptions are stated in the next group of bullets. For example, each stack carried by a war tortoise must be worth less than 5,000,000 coins.
• This means that tradeable items worth over 5,000,000 each cannot be carried, because a "stack" of such an item always has at least one of that item. Items that go over the Grand Exchange market value the familiar can hold will give the message "This item is too valuable to trust to this familiar."
• A particularly valuable stack such as 200 noted rune 2h swords cannot be fully carried by a BoB, even if one tries to make two stacks of 100 each.
• Rune and pure essence can be carried only by the three abyssal familiars, which can only carry essence (see below).
• Many untradeable items which are "supplies" but not "equipment" can be carried. The idea is that these are items used in skilling where more than 28 inventory spots could be useful. This is only a guideline, and one should test items beforehand. For example, the following can be carried:
  • All untradeable potions which are not quest items.
  • Enchanted gems (the post-hoc reasoning is that they are crafting supplies that one buys from Slayer Masters).
  • Rings of slaying and ferocious rings.
  • Mining urns (r) but not cooking urns (r). (The post-hoc reasoning is that it's useful to bring lots of mining urns in a BoB, but one never needs several cooking urns).
  • Saplings.
  • Red sandstone and crystal-flecked sandstone.
• Many other untradeable items cannot be carried.

Additionally, familiars cannot hold restricted trade items along with the following tradeables:

• Bonds
• Summer Beach Party tokens (any year)
• Crafting catalyst items (metal setting, leather case, gem focus, summoning focus)
• Parasols
• Spring Fayre tokens

Currently the limit is 5,000,000 coins. The limit is based on the Grand Exchange market values of items. For example, a beast of burden will carry a rune full helm, but not a drygore mace.

The amount a familiar could hold was changed with the release of summoning patch #2. There is speculation that it was changed because people were complaining about the limited amount of items a player could store with the familiars.

For large volume resource collection, combine a beast of burden familiar with imp-in-a-box. Use imps to send your resources and empty imp boxes to the bank, then fill up your familiar and your inventory and travel back to the bank. This will allow you to transport 28 items in your inventory + 28 items banked by the imps (+banked boxes) + your familiar's cargo space worth of items.

It should however be noted that hunting imps takes a long time and it might be simpler to just bank more often.

For quest items that cannot be handed to a familiar, the method above still works. Simply hand your empty magic boxes to your familiar until it is full, then ship the remaining empty boxes to your bank with imps from occupied boxes. In each case, the sums come out the same. Imps either take one item and one magic box home, or the box is handed to the familiar, and the imp carries two items home.

Beast of Burden limitations

Although in most cases a beast of burden helps, there are a few factors that should be taken into consideration before using it.

Premature death

If a beast of burden dies while carrying items, they will be dropped on the floor and players may not be able to retrieve them if they do not have inventory slots available. Players may want to think about how many items they load a familiar with depending on what situation they will be in, such as in a fight where the beast of burden can be attacked by a player or monster, and how much they should carry to combat it. It should be noted that beasts of burden are immune to poison and most should have more than enough life points to get through the situation.

Familiar timer

All familiars have a set lifespan - including beasts of burden. The timer is a key factor to take into consideration. Players should consider how long a trip might take, or the familiar's timer might end up running out. If the familiar is being used to bring items back and not to carry them, consider waiting until it is really needed before summoning.

On 29 April 2009, an update allowed players to replenish the familiar's lifespan. They are required to have both the pouch of the familiar they currently have, and have the summoning points that would otherwise be required to summon a new one. Pouches can be used on the familiar to do this, or the familiar interface may be used.

Training production skills

For the production skills of Smithing, Crafting, Herblore, Divination, and Cooking, the production action brings up a "Make-X" interface. By default, this interface allows the player to press "Space" to create the "maximum possible" number of items possible before certain item-saving effects. For example, 15 unfinished potions and 13 secondaries gives the option to make 13, even though it is very common to be able to make more than 13 with the scroll of cleansing.

Curiously, this "maximum possible" includes the BoB's inventory. Thus, if a player has a war tortoise, 14 unfinished potions and 14 secondaries in the normal inventory, and 9 unfinished potions and 9 secondaries in the war tortoise's inventory, then by default, the Make-X option is 23. However, if the player simply presses space from this menu and does nothing else, then the supplies in the inventory will run out after 14 potions. An interesting way around this is to constantly click the "Take Beast of Burden items" button from the familiar interface (in inventory view mode). This does not interrupt the skilling action, but it allows the player to produce more than 14 potions in a row in this case.

As a more drastic example, consider the production of overloads. This requires 6 items. Using only the normal inventory with 28 spots, one can make at most 4 overloads per inventory. However, by using a pack yak, the total capacity increases to 58 effective spots. One can thus create 9 overloads per inventory, but the player must keep clicking "Take Beast of Burden items" or else they will end production early. Producing overloads is already a click intensive activity, so adding a few different clicks from the BoB interaction to greatly decrease banking time is recommended. A bank preset can be configured to take a certain BoB setup. In other circumstances, the extra clicks from the BoB action might not be considered worthwhile.

Other beasts of burden

The following familiars can only be summoned while training Dungeoneering in Daemonheim.

The following Beast of Burden Clay familiars are exclusive to the Stealing Creation activity.

Glitches

• There was a glitch with beasts of burden when using Cyreg Paddlehorn's boat (to or from Mort'ton). When a beast of burden was following a player, the beast would be forcefully dismissed, dropping all of the items it was carrying. There was no way to pick up the items from the boat. The messages only appeared after arriving at the destination and dismissing the message that informs the player of the arrival. This has since been fixed.
• During a God Wars Dungeon instance, occasionally a player's beast of burden would vanish with the items inside regardless of the timer; the only way to reobtain the items from the familiar was either to summon a new one or use the deposit familiar option at the bank. This is now fixed.
• One can encounter display glitches when dragging items between the inventory and the BoB's inventory (in either direction) while teleporting. The glitch that occurs is that the item may become invisible. To fix this, one can try to transfer another item after one is done teleporting. This glitch occurs frequently when managing inventory space during farm runs while using a BoB. This glitch occurs because the player has a different status while teleporting. For example, immediately after using a lodestone teleport, spamming a key bound to "surge" will yield the error that the player is invisible.