|Release date||22 May 2012 (Update)|
|XP per kill||661 (and 218.1 experience)|
|Always drops||Big bones|
|Examine text||The final stage of a grotworm before its metamorphosis.|
|Assigned by||Turael or Spria, Mazchna or Achtryn, Chaeldar, Sumona, Vannaka, Duradel or Lapalok, Kuradal, Morvran|
Mature grotworms are monsters that can be found on the bottom level of the Grotworm Lair. They have slow, but accurate and hard-hitting magic and melee attacks. However, magic attacks are only used on players outside of melee range, similar to monsters such as metal dragons and cockroach soldiers. It is possible to safespot them using the pillars if you stand far enough back from them. Lower-level players are recommended to bring high healing food such as monkfish or sharks. Ranged/magic would require Protect from Magic/Deflect Magic if using safe spots. The magic attack has a short range, so flashing your prayer when out of its range can help conserve prayer points. Despite their ranged weakness, a player with 70+ melee stats should have little trouble killing them efficiently, even without the use of prayer.
Using high level ranged gear such as Armadyl and using a bunyip will reduce the need for prayer potions/flasks. The occasional Shark drops will reduce the need for food, and ranged gear will mean little damage from the mature grotworms' magic attack while ranging.
If a player tries to set up a cannon within the Grotworm Lair, they will receive a message saying: "The damp air would prevent your cannon operating." This does not prevent hand cannons from working, however.
Some players may find it useful to bring runes to cast High Level Alchemy on the items dropped by the grotworms, as adamant and rune equipment are common drops. The profit of using this spell on some of these items is greater than banking and selling them.
Item Quantity Rarity GE market price Big bones 1 Always 546
- Represents 90% confidence range, based on a sample of 7,049 kills.
1 charm is dropped at a time.
- Please add to the log (only if 50 or more creatures killed).
Weapons and ArmourEdit
Item Quantity Rarity GE market price Adamant chainbody 1 Common 2,278 Adamant sq shield 1 Common 1,740 Rune dagger 1 Common 4,255 Rune helm 1 Common 10,658 Rune mace 1 Common 7,957 Rune longsword 1 Common 18,368 Royal cape 1 Rare 381
Item Quantity Rarity GE market price Grimy guam 1 Uncommon 429 Grimy marrentill 1 Uncommon 95 Grimy tarromin 1 Uncommon 30 Grimy harralander 1 Uncommon 80 Grimy ranarr 1 Rare 2,305 Grimy irit 1 Rare 1,752 Grimy avantoe 1 Rare 3,245 Grimy kwuarm 1 Rare 2,950 Grimy cadantine 1 Very rare 1,820 Grimy lantadyme 1 Very rare 7,374 Grimy dwarf weed 1 Very rare 7,309
Item Quantity Rarity GE market price Fellstalk seed  2 Common 928 Belladonna seed 1 Rare 83 Cactus seed 1 Rare 40 Poison ivy seed 1 Rare 9 Toadflax seed 1 Uncommon 818 Irit seed 1 Rare 188 Avantoe seed 1 Rare 2,141 Kwuarm seed 1 Rare 66 Snapdragon seed 1 Very rare 2,379 Cadantine seed 1 Very rare 654 Lantadyme seed 1 Very rare 27,775 Dwarf weed seed 1 Very rare 30,322 Torstol seed 1 Very rare 18,952
- ^ No anagogic ort is dropped along this drop.
Item Quantity Rarity GE market price Flax 50 (noted) Common 4,950 Runite ore 1 Common 11,271 Adamantite ore 3 (noted) Common 4,083 Royal dragonhide 1 Uncommon 4,954
Item Quantity Rarity GE market price Coins 1,000 – 5,000 Common Not sold Saradomin brew (2) 1 Common 620 Shark 2 Common 2,006 Blood rune 20 Common 9,620 Long bone 1 Rare Not sold Curved bone 1 Rare Not sold Clue scroll (hard) 1 Rare Not sold Spirit sapphire 1 Rare Not sold Spirit emerald 1 Rare Not sold Spirit ruby 1 Rare Not sold Court summons 1 Very rare Not sold Starved ancient effigy 1 Very rare Not sold
Rare drop table dropsEdit
- This monster has access to the rare drop table.
The ring of wealth is not required to access the table.
Show/hide rare drop table Item Quantity Rarity GE Market Price Coins 200–350,3,000 Common Not sold Uncut sapphire 1 Common 1,353 Uncut emerald 1 Common 2,509 Uncut ruby 1 Common 2,766 Uncut diamond 1 Uncommon 5,242 Loop half of a key 1 Uncommon 31,242 Tooth half of a key 1 Uncommon 32,820 Uncut dragonstone 1 Rare 14,500 Dragonstone 1 Rare 10,089 Dragon dagger 1 Uncommon 16,655 Rune battleaxe 1 Rare 24,265 Rune javelin 5 Rare 915 Adamant javelin 20 Very rare 1,240 Rune 2h sword 1 Very rare 37,404 Rune spear 1 Very rare 11,415 Dragon spear 1 Very rare 36,976 Battlestaff 200 (noted) Rare 1,567,200 Rune sq shield 1 Very rare 22,125 Rune kiteshield 1 Very rare 31,681 Shield left half 1 Very rare 64,841 Dragon helm 1 Very rare 59,361 Adamant bolts 200 Uncommon 13,000 Onyx bolts 150 Rare 1,257,150 Rune arrow 150 Rare 22,650 Vecna skull 1 Very rare 97,624 Water talisman 1 Uncommon 10,576 Earth talisman 25–35 (noted) Uncommon 63,200–88,480 Fire talisman 25–35 (noted) Uncommon 61,425–85,995 Chaos talisman 1 Uncommon 684 Nature talisman 1 Uncommon 486 Pure essence 1,000–1,500 (noted) Uncommon 17,000–25,500 Nature rune 60–80 Rare 18,360–24,480 Soul rune 20 Rare 4,480 Law rune 45 Rare 19,350 Death rune 50 Rare 14,100 Blood rune 50 Rare 24,050 Raw swordfish 125–250 (noted) Uncommon 58,750–117,500 Raw shark 250 (noted) Uncommon 297,750 Big bones 150–180 (noted) Uncommon 81,900–98,280 Coal 550–700 (noted) Uncommon 132,550–168,700 Adamantite ore 150–250 (noted) Uncommon 204,150–340,250 Silver ore 100 (noted) Rare 8,600 Runite ore 100 (noted) Rare 1,127,100 Rune bar 1 Common 14,239 Rune bar 50 (noted) Very rare 711,950 Clean toadflax 35–45 (noted) Uncommon 112,805–145,035 Clean snapdragon 30–35 (noted) Uncommon 103,950–121,275 Clean torstol 16–34 (noted) Uncommon 89,616–190,434 Snapdragon seed 1 Common 2,379 Torstol seed 1 Uncommon 18,952 Watermelon seed 3 Uncommon 8,724 Magic seed 3–7 Rare 484,107–1,129,583 Palm tree seed 10 Rare 1,223,390 Yew logs 450–550 (noted) Rare 165,150–201,850 Crystal triskelion fragment 1 1 Very rare Not sold Crystal triskelion fragment 2 1 Very rare Not sold Crystal triskelion fragment 3 1 Very rare Not sold Brawling gloves (Melee) 1 Very rare Not sold Brawling gloves (Magic) 1 Very rare Not sold Brawling gloves (Ranged) 1 Very rare Not sold Brawling gloves (Agility) 1 Very rare Not sold Brawling gloves (Cooking) 1 Very rare Not sold Brawling gloves (FM) 1 Very rare Not sold Brawling gloves (Fishing) 1 Very rare Not sold Brawling gloves (Hunter) 1 Very rare Not sold Brawling gloves (Mining) 1 Very rare Not sold Brawling gloves (Prayer) 1 Very rare Not sold Brawling gloves (Smithing) 1 Very rare Not sold Brawling gloves (Thieving) 1 Very rare Not sold Brawling gloves (WC) 1 Very rare Not sold
- Universal drops are dropped by nearly every monster outside of Daemonheim.
- These drops are dropped alongside main drops.
Item Quantity Rarity GE market price Key token 1 Rare Not sold
- When these creatures were first released, they did not drop items from the rare drop table, but did after the Queen Black Dragon update.
- The word 'grotworm' means caveworm in Dutch.
- Their examine text hints towards the possibility of the existence of a stronger grotworm based creature, although likely not an actual worm as "metamorphosis" implies, but none were released with them.
- On 17 June 2013, these monsters received a massive power increase. Their lifepoints more than tripled, their accuracy was increased greatly, and their damage output was made substantially higher. This considerably decreased the amount of botting and people in general coming to the grotworms for money. They were level 120 with 3000 lifepoints before this update.
- On the same 17 June 2013 update, the slayer experience rewarded increased from 73 to 360.5, to compensate for their increased strength.
- Due to excessive botting, an update on 7 August 2012 removed several rune armour drops from the drop table of mature grotworms, replacing them with their adamant counterparts, making it less effective to earn money. The same update also removed royal bolts and super restore potions from their drop tables.