|Release date||22 May 2012 (Update)|
|Combat level|| 98|
|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|
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 609
- Represents 90% confidence range, based on a sample of 5,913 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 2,288 Adamant sq shield 1 Common 1,708 Rune dagger 1 Common 4,230 Rune helm 1 Common 10,744 Rune mace 1 Common 7,786 Rune longsword 1 Common 18,324 Royal cape 1 Rare 241
Item Quantity Rarity GE Market Price Grimy guam 1 Uncommon 718 Grimy marrentill 1 Uncommon 94 Grimy tarromin 1 Uncommon 35 Grimy harralander 1 Uncommon 166 Grimy ranarr 1 Rare 3,038 Grimy irit 1 Rare 2,789 Grimy avantoe 1 Rare 4,165 Grimy kwuarm 1 Rare 4,309 Grimy cadantine 1 Very rare 2,130 Grimy lantadyme 1 Very rare 8,750 Grimy dwarf weed 1 Very rare 9,828
Item Quantity Rarity GE Market Price Fellstalk seed  2 Uncommon 1,858 Belladonna seed 1 Rare 80 Cactus seed 1 Rare 17 Poison ivy seed 1 Rare 5 Toadflax seed 1 Uncommon 2,379 Irit seed 1 Rare 232 Avantoe seed 1 Rare 2,273 Kwuarm seed 1 Rare 1,362 Snapdragon seed 1 Very rare 1,574 Cadantine seed 1 Very rare 805 Lantadyme seed 1 Very rare 31,111 Dwarf weed seed 1 Very rare 39,056 Torstol seed 1 Very rare 25,443
- ^ No anagogic ort is dropped along this drop.
Item Quantity Rarity GE Market Price Flax 50 (noted) Common 4,450 Runite ore 1 Uncommon 11,215 Adamantite ore 3 (noted) Common 5,226 Royal dragonhide 1 Uncommon 5,411
Item Quantity Rarity GE Market Price Coins 5,000 Common Not sold Saradomin brew (2) 1 Common 636 Shark 2 Common 3,258 Blood rune 50 Common 14,300 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 250 – 450; 3,000;
9,000; 10,000; 12,000
Common Not sold Uncut sapphire 1 Common 1,321 Uncut emerald 1 Common 2,717 Uncut ruby 1 Common 3,697 Uncut diamond 1 Uncommon 6,310 Loop half of a key 1 Uncommon 17,967 Tooth half of a key 1 Uncommon 39,712 Uncut dragonstone 1 Rare 15,490 Dragonstone 1 Rare 10,122 Dragon dagger 1 Uncommon 16,403 Rune battleaxe 1 Rare 24,212 Rune javelin 5 Rare 875 Adamant javelin 20 Very rare 1,220 Rune 2h sword 1 Very rare 37,208 Rune spear 1 Very rare 11,355 Dragon spear 1 Very rare 36,221 Dragon dagger 50 (noted) Very rare 820,150 Rune sq shield 1 Very rare 22,377 Rune kiteshield 1 Very rare 31,544 Shield left half 1 Very rare 64,669 Dragon helm 1 Very rare 58,890 Adamant bolts 200 Uncommon 16,600 Onyx bolts 150 Rare 1,263,150 Rune arrow 150–200, 500 Rare 22,650–75,500 Battlestaff 200 (noted) Rare 1,597,200 Vecna skull 1 Very rare 89,644 Water talisman 1 Uncommon 13,788 Earth talisman 25–35 (noted) Uncommon 100,500–140,700 Fire talisman 25–35 (noted) Uncommon 100,675–140,945 Chaos talisman 1 Uncommon 1,004 Nature talisman 1 Uncommon 277 Pure essence 500–15,000 (noted) Uncommon 9,500–285,000 Nature rune 20–80 Rare 5,600–22,400 Soul rune 20 Rare 3,580 Law rune 45 Rare 13,950 Death rune 50, 121 Rare 9,350–22,627 Blood rune 50 Rare 14,300 Raw swordfish 125–250, 1,000 (noted) Uncommon 49,750–398,000 Raw shark 250–500 (noted) Uncommon 431,000–862,000 Big bones 150–500 (noted) Uncommon 91,350–304,500 Coal 150–7,500 (noted) Uncommon 35,550–1,777,500 Adamantite ore 150–800 (noted) Uncommon 261,300–1,393,600 Silver ore 100 (noted) Rare 9,500 Runite ore 100 (noted) Rare 1,121,500 Adamant bar 1,000–7,000 (noted) Rare 2,950,000–20,650,000 Rune bar 1, 50 (noted) Rare 14,228–711,400 Clean toadflax 25–250 (noted) Uncommon 134,025–1,340,250 Clean snapdragon 30–120 (noted) Uncommon 129,150–516,600 Clean torstol 10–100 (noted) Uncommon 87,260–872,600 Watermelon seed 3 Uncommon 5,982 Yew seed 1–50 Rare 68,397–3,419,850 Magic seed 1–7 Rare 116,711–816,977 Palm tree seed 10 Rare 1,118,630 Snapdragon seed 1 Rare 1,574 Yew logs 50–20,000 (noted) Rare 20,650–8,260,000 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.