Solak

Solak, the Grove Guardian is one of the Guardians of Guthix and can be fought at The Lost Grove. He was released on 29 May 2018 and is deemed as one of the strongest bosses in-game, with 8 million life points and drops including tier 92 dual-wield blightbound crossbows.

During the fight players fight alongside Merethiel, who plays a significant role in the lore behind Solak.

There is a hard cap of seven players to fight Solak, though there is also a vastly harder duo mode, which causes different mechanics to take effect. The fight has "multiple health bars" in each phase along with sub-attacks that it will use alongside normal and special attacks.

Defeating Solak is required for The Reaper title which remains required for the completionist cape.. Solak is a requirement for the Final Boss and Insane Final Boss titles. The suffix title "Guardian of the Grove" is achieved from obtaining all drops from Solak's collection log.

Drops
There will be a main drop table and a secondary drop table containing items such as effigies, crystal triskelion fragments, and clue scrolls. Solak will also drop a boss pet, Solly, which will have a drop rate of 1 in 1200 with a threshold of 500.

Dying during a kill where the team successfully completes the kill will result in the player being marked as being owed loot, as long as they remain on the same world.

History
Solak is a creature of the Anima Mundi, like Vorago and Telos, and a Guardian of Guthix who defends the Lost Grove from those who want its power. He is referred by the inhabitants of the grove as a "walker".

Solak was tasked in protecting an island that is inhabited by smaller creatures of the Anima Mundi. During the Second Age, Seren sent four elite elf warriors to aid Solak in his task. However, one of these elves, Eredthor, became tempted by the power of the grove and attacked Solak in an attempt to control it. The fairy Bub thinks of the elf as pure darkness. Eredthor was defeated through the combined efforts of his three former companions and Solak, sealing half of his mind within Solak himself and the other half within a stone in Merethiel's possession.

After this battle, Solak ordered the elves to depart and disappeared along with the other walkers, sealing the grove off from the world. During his disappearance the fairies tried everything to see him return, where even humans were said to have built temples worshipping him, which led the religion to die out as he never responded. The grove would not be in contact with the outside world until the fifth year of the Sixth Age. Solak is currently corrupted by a mental manifestation of Eredthor.

Trivia

 * It was revealed at RuneFest by Mod Pi that Solak was originally called Kalos.
 * Solak's initial concept art was changed after it drew comparisons to champion Maokai.
 * Solak will be voiced by, an actor and director who also played Geralt of Rivia in game series.