so this is here to help people in getting the trolls. where to find them and how to do them all at once if you wish.

Its important to know that as soon as you kill a bonus troll you get credit for it even if you fail. Playing with randoms can be difficult to get all 3 in one match so just doing one at a time is frequently a better choice.

In order to do all 3 at once if you wish you will need to do the stages in order

Wheel>Water>Cog

its worth noting you can do wheel or water first. so long as cog is last. i just do this in this order because it got ingrained while i was working it out lol.

if anyone has a complete info on the side bosses i would appreciate it. Usually teams just hack and slash with no consideration of their buffs and debuffs lol.

EDIT: after running this 30 or so times with randoms i think a better order is Water -> Wheel -> Cog. The reason is when you turn on the water it floods the dry areas in the other maps. Normally the enemy would be able to swarm across the dry areas hitting you everywhere but with them flooded it limits the enemy to hitting you head on or in very controllable kill boxes. Seems to work smoother with random players.

Once you finish killing the first troll you immediately enter a room that holds your first 2 barrels. when you enter the next section of that room with the long hall there are 2 side pathways.

check these sides for a 3rd barrel. if the barrel is not in these side halls it will be in the next room where you fight the next set of trolls. you will need all 3 barrels if you want to kill all 3 trolls in one match. if you even lose one you cannot get all 3 bosses in one match.
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once you get into this room clear out the mobs and immediately stuff the 3 barrels into this corner of the room. this will keep the barrels away from enemy spawns and generally safe during the troll fight.
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kill the trolls and be mindful of the mob that spawns when the ladder comes down. Then move your barrels into the next room again clearing the mobs and stuffing them in a safe corner.


now onto the first boss.

remember the order Wheel -> Water -> Cog

The wheel will need 2 barrels so leave one behind and take the 2.

We do this one first because the wheel will open up other barrels on water and cog. The lever you pull to move the wheel and open up the plank wall also opens up barrel areas on water and cog.


A - This is where the boss is. We need to drop the drawbridge first.

C - if you had done the water first this would be a elevator you could trigger that would have a barrel in it, but since we did not. Its useless.

B - To drop the drawbridge hop here.


once here break this piece of wood.
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go back up to the drawbridge, and creep to the edge. if you fall holding the barrel when you are picked back up you will still be holding the barrel. Toss the barrel here, its got a pretty wide area so its hard to miss.



the other drawbridge will fall, take your other barrel cross and you are at boss troll 1.

Now onto Water

you should have one barrel left. take it into Water. Shortly after entering theres a side entrance to the right. Normally it is blocked by planks but by doing wheel it is now opened up. This side entrance leads to a path. Follow it up.


Once you get to a point you will see another area opened up that was previously blocked. Inside is the 2nd barrel you need. Grab it.


continue following the path babysitting your barrels till you get here. Then hop up the stairs and to the left and you are at boss 2.


kill off the boss continue up the steps pull the lever and hop back to the main room.

Cog

DO NOT GRAB the Lever to release the COG. doing so will trigger endless mobs.

Now we did the other two rooms first for a reason. Cog room has 2 barrels in it. Wheel opened one. Water the other.

The room is LOADED with assassins. Clear out the mobs before you move on first.

Then hop back to the water wheel in the room.


on the other side of the water wheel is a lever, pull it. it will raise a barrel to the top of the bridge. Ignore that for the moment.

Behind the water wheel opposite the lever is a cave with another barrel in it opened by the wheel room we did earlier. grab both barrels and head across the bridge up top.


now hop back to the bridge with both barrels and follow this path. at the end is a cave leading to troll 3. finish him off grab the cog and finish the mission.

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along the river by the waterfall falling into a pool, on the middle rock is a dead dwarf with keys. hes supposed to open locked doors but not idea where they are. if anyone knows let me know :)