|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 657
- Represents 90% confidence range, based on a sample of 5,762 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 2,376 Adamant sq shield 1 Common 1,781 Rune dagger 1 Common 4,358 Rune helm 1 Common 10,706 Rune mace 1 Common 7,721 Rune longsword 1 Common 18,273 Royal cape 1 Rare 249
Item Quantity Rarity GE Market Price Grimy guam 1 Uncommon 937 Grimy marrentill 1 Uncommon 81 Grimy tarromin 1 Uncommon 34 Grimy harralander 1 Uncommon 208 Grimy ranarr 1 Rare 3,179 Grimy irit 1 Rare 3,087 Grimy avantoe 1 Rare 4,798 Grimy kwuarm 1 Rare 4,778 Grimy cadantine 1 Very rare 2,179 Grimy lantadyme 1 Very rare 9,093 Grimy dwarf weed 1 Very rare 10,852
Item Quantity Rarity GE Market Price Fellstalk seed  2 Uncommon 1,526 Belladonna seed 1 Rare 89 Cactus seed 1 Rare 20 Poison ivy seed 1 Rare 4 Toadflax seed 1 Uncommon 2,278 Irit seed 1 Rare 335 Avantoe seed 1 Rare 2,771 Kwuarm seed 1 Rare 903 Snapdragon seed 1 Very rare 2,045 Cadantine seed 1 Very rare 839 Lantadyme seed 1 Very rare 34,066 Dwarf weed seed 1 Very rare 49,171 Torstol seed 1 Very rare 24,352
- ^ No anagogic ort is dropped along this drop.
Item Quantity Rarity GE Market Price Flax 50 (noted) Common 3,800 Runite ore 1 Uncommon 11,307 Adamantite ore 3 (noted) Common 6,057 Royal dragonhide 1 Uncommon 5,632
Item Quantity Rarity GE Market Price Coins 5,000 Common Not sold Saradomin brew (2) 1 Common 428 Shark 2 Common 3,460 Blood rune 50 Common 13,000 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 1,434 Uncut emerald 1 Common 2,772 Uncut ruby 1 Common 3,643 Uncut diamond 1 Uncommon 6,590 Loop half of a key 1 Uncommon 19,005 Tooth half of a key 1 Uncommon 40,326 Uncut dragonstone 1 Rare 15,867 Dragonstone 1 Rare 10,138 Dragon dagger 1 Uncommon 16,300 Rune battleaxe 1 Rare 24,136 Rune javelin 5 Rare 900 Adamant javelin 20 Very rare 1,200 Rune 2h sword 1 Very rare 37,522 Rune spear 1 Very rare 11,387 Dragon spear 1 Very rare 36,336 Dragon dagger 50 (noted) Very rare 815,000 Rune sq shield 1 Very rare 22,348 Rune kiteshield 1 Very rare 31,840 Shield left half 1 Very rare 63,812 Dragon helm 1 Very rare 59,386 Adamant bolts 200 Uncommon 20,600 Onyx bolts 150 Rare 1,264,050 Rune arrow 150–200, 500 Rare 21,600–72,000 Battlestaff 200 (noted) Rare 1,635,800 Vecna skull 1 Very rare 90,593 Water talisman 1 Uncommon 12,984 Earth talisman 25–35 (noted) Uncommon 87,225–122,115 Fire talisman 25–35 (noted) Uncommon 93,875–131,425 Chaos talisman 1 Uncommon 984 Nature talisman 1 Uncommon 303 Pure essence 500–15,000 (noted) Uncommon 7,500–225,000 Nature rune 20–80 Rare 5,640–22,560 Soul rune 20 Rare 3,020 Law rune 45 Rare 11,880 Death rune 50, 121 Rare 6,950–16,819 Blood rune 50 Rare 13,000 Raw swordfish 125–250, 1,000 (noted) Uncommon 52,750–422,000 Raw shark 250–500 (noted) Uncommon 441,000–882,000 Big bones 150–500 (noted) Uncommon 98,550–328,500 Coal 150–7,500 (noted) Uncommon 34,200–1,710,000 Adamantite ore 150–800 (noted) Uncommon 302,850–1,615,200 Silver ore 100 (noted) Rare 10,600 Runite ore 100 (noted) Rare 1,130,700 Adamant bar 1,000–7,000 (noted) Rare 3,215,000–22,505,000 Rune bar 1, 50 (noted) Rare 14,190–709,500 Clean toadflax 25–250 (noted) Uncommon 129,700–1,297,000 Clean snapdragon 30–120 (noted) Uncommon 127,020–508,080 Clean torstol 10–100 (noted) Uncommon 73,460–734,600 Watermelon seed 3 Uncommon 6,624 Yew seed 1–50 Rare 66,914–3,345,700 Magic seed 1–7 Rare 133,460–934,220 Palm tree seed 10 Rare 1,045,090 Snapdragon seed 1 Rare 2,045 Yew logs 50–20,000 (noted) Rare 20,000–8,000,000 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.