|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 544
- Represents 90% confidence range, based on a sample of 6,660 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 2,254 Adamant sq shield 1 Common 1,809 Rune dagger 1 Common 4,211 Rune helm 1 Common 10,624 Rune mace 1 Common 7,756 Rune longsword 1 Common 18,329 Royal cape 1 Rare 367
Item Quantity Rarity GE market price Grimy guam 1 Uncommon 495 Grimy marrentill 1 Uncommon 95 Grimy tarromin 1 Uncommon 37 Grimy harralander 1 Uncommon 134 Grimy ranarr 1 Rare 3,357 Grimy irit 1 Rare 2,943 Grimy avantoe 1 Rare 4,594 Grimy kwuarm 1 Rare 3,790 Grimy cadantine 1 Very rare 2,405 Grimy lantadyme 1 Very rare 8,967 Grimy dwarf weed 1 Very rare 9,042
Item Quantity Rarity GE market price Fellstalk seed  2 Common 1,024 Belladonna seed 1 Rare 66 Cactus seed 1 Rare 37 Poison ivy seed 1 Rare 10 Toadflax seed 1 Uncommon 960 Irit seed 1 Rare 191 Avantoe seed 1 Rare 2,595 Kwuarm seed 1 Rare 126 Snapdragon seed 1 Very rare 2,335 Cadantine seed 1 Very rare 747 Lantadyme seed 1 Very rare 30,994 Dwarf weed seed 1 Very rare 37,873 Torstol seed 1 Very rare 26,997
- ^ No anagogic ort is dropped along this drop.
Item Quantity Rarity GE market price Flax 50 (noted) Common 4,150 Runite ore 1 Common 10,441 Adamantite ore 3 (noted) Common 5,262 Royal dragonhide 1 Uncommon 5,749
Item Quantity Rarity GE market price Coins 5,000 Common Not sold Saradomin brew (2) 1 Common 660 Shark 2 Common 2,256 Blood rune 20 Common 8,820 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 1,365 Uncut emerald 1 Common 2,872 Uncut ruby 1 Common 3,404 Uncut diamond 1 Uncommon 5,655 Loop half of a key 1 Uncommon 30,596 Tooth half of a key 1 Uncommon 36,191 Uncut dragonstone 1 Rare 14,893 Dragonstone 1 Rare 10,151 Dragon dagger 1 Uncommon 16,150 Rune battleaxe 1 Rare 24,244 Rune javelin 5 Rare 885 Adamant javelin 20 Very rare 1,240 Rune 2h sword 1 Very rare 37,376 Rune spear 1 Very rare 11,148 Dragon spear 1 Very rare 36,181 Battlestaff 200 (noted) Rare 1,456,000 Rune sq shield 1 Very rare 22,401 Rune kiteshield 1 Very rare 31,624 Shield left half 1 Very rare 64,211 Dragon helm 1 Very rare 58,935 Adamant bolts 200 Uncommon 12,400 Onyx bolts 150 Rare 1,276,950 Rune arrow 150 Rare 22,650 Vecna skull 1 Very rare 111,748 Water talisman 1 Uncommon 16,593 Earth talisman 25–35 (noted) Uncommon 145,850–204,190 Fire talisman 25–35 (noted) Uncommon 142,825–199,955 Chaos talisman 1 Uncommon 809 Nature talisman 1 Uncommon 514 Pure essence 1,000–1,500 (noted) Uncommon 16,000–24,000 Nature rune 60–80 Rare 17,400–23,200 Soul rune 20 Rare 3,840 Law rune 45 Rare 17,595 Death rune 50 Rare 11,100 Blood rune 50 Rare 22,050 Raw swordfish 125–250 (noted) Uncommon 56,750–113,500 Raw shark 250 (noted) Uncommon 352,000 Big bones 150–180 (noted) Uncommon 81,600–97,920 Coal 550–700 (noted) Uncommon 139,150–177,100 Adamantite ore 150–250 (noted) Uncommon 263,100–438,500 Silver ore 100 (noted) Rare 8,700 Runite ore 100 (noted) Rare 1,044,100 Rune bar 1 Common 14,355 Rune bar 50 (noted) Very rare 717,750 Clean toadflax 35–45 (noted) Uncommon 152,880–196,560 Clean snapdragon 30–35 (noted) Uncommon 156,600–182,700 Clean torstol 16–34 (noted) Uncommon 125,552–266,798 Snapdragon seed 1 Common 2,335 Torstol seed 1 Uncommon 26,997 Watermelon seed 3 Uncommon 5,550 Magic seed 3–7 Rare 416,295–971,355 Palm tree seed 10 Rare 1,234,780 Yew logs 450–550 (noted) Rare 164,700–201,300 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.
- 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.