Primary
To locate Blade Scout Ryder, follow the path until you get to point A on the map. Do the bonus as described below if you want to. Now pick up one of three Vine Seeds at point A. If solo, you must return back here for the other two seeds, after you build a bridge; thus a party of 3 seed carriers is recommended. Sometimes only one or two seeds spawn; more seeds can be found at point 2 on the map (on the bonus path), and at point C on the map. At the locations marked B on the map use the seed to create a bridge that enables you to traverse the jungle. Return to seed point to fetch another seed to build another bridge. After crossing the second bridge, talk to Blade Scout Ryder, who will send you on your own to defeat the White Mantle. You will need a fourth seed, which you can fetch from point C on map. In order to complete the mission, you need to defeat a large group of White Mantle and their boss Justiciar Hablion.

Note: that while fighting near the Bloodstone you will be under influence of the environment effect Curse of the Bloodstone, which makes resurrection skills take 4 times as long to cast.

Note: It is possible to "waste" vine seeds by dropping them on a glowing circle of a bridge that has already been grown. The worst-case scenario would be using up all the remaining vine seeds and thus getting stuck, forcing a mission restart. (There are 3 max seeds at point A and another max 3 seeds at point C.) Before you give up on mission check the lower watery area for more seeds (added patch). You can find approximately 4-7 bonus seeds.

Bonus
Do the mission as normal until you reach point A on the map. Grab a seed and go back the way you came. After a short distance, to the south of the path - in the gray swamplike area - you should notice a path leading up to a gray platform with an orange rune on it. Drop one of the seeds on the platform (1 on the map).

A druid will appear and ask for your aid in awakening the Elder Druid. You will need to free three more druids by dropping seeds on their platforms. You get the seeds from position 2 on the map and drop them at the destinations marked 3 on the map. These druids and the original will then move up to a large platform and awaken the Elder Druid.

However, while doing this you will be attacked by Jungle Guardians, which the druid says you must not kill. If you do, you will anger the spirits of the jungle, causing several Ravagers to spawn and preventing the other druids from appearing when you attempt to activate their platforms (more Ravagers will spawn instead). This means you will be unable to complete the bonus, so you must follow the druid's instructions and avoid killing the Guardians; luckily, they don't follow very far, so they shouldn't be much more than a nuisance.

If you have any henchmen in the party, use the compass flags to force them to move past the Guardians. Plant flags on the main screen, not on radar, as if you place a flag in an area that henchmen cannot reach, they'll give up on it and stop to fight. If you have any heroes, you can simply set them to "Avoid Combat" mode. Be sure to disable pets and offensive spirits, too, as a hero can still use these to kill a jungle guardian. Due to the uncontrollability of animated minions, it is strongly recommended that you let any allied minions die off before entering the bonus area.

Note: that the druid to the east can be reached without carrying a seed past any jungle guardians if you go under the log bridge. The map currently shows the wrong path. You do have to run past jungle guardians to deliver the north seed, though. Flag any henchmen far away, as they will come a considerable distance to attack jungle guardians that attack the seed runner. Running skills, self-healing, healing over time, and very long range heals from other characters can help protect the seed runner.

Once the Elder Druid is summoned (point 4), speak to him to complete the bonus. The Jungle Guardians will remain hostile, although they will now ignore you unless you attack them first. If the group's seed runner dies while running back after dropping a seed at the last druid, completing the bonus first will make it easier to resurrect him.

If continuing on with the mission, you can either backtrack the way you came, or you can continue north past the guardians and follow an alternate route (blue path on the map) to return to the main mission path. There is one bridge you have to create. The seed for it is very close, in the water.

Bug! The first druid may get stuck on an obstacle, such as a chest or the Jungle Guardians. If it gets stuck on a Guardian, you will need to aggro guardians and try to get them follow you. If it gets stuck on a chest, though, you will have to restart the mission.

Tip: This bonus can be done solo. Most of the enemies on the way to the first druid can be run past with little trouble, and only the Wind Riders pose any real threat, due to health degeneration, enchantment removal, and interruption; however they are fragile. Bring running skills such as Sprint, Dodge, etc., as well as self-heals. Once you reach the Guardian area, the rest of the bonus is rather easy as long as you are careful.