Posting a solution with the complete Spawn Timers for Junkenstein's Revenge. The other solutions have good strategies to follow.
The base spawns and difficulty for the Halloween Terror Challenge Missions are identical to an Expert Junkenstein's Revenge run.
The only difference is the variant for the particular challenge which in this case is:
Every 60 seconds your heroes are swapped at random.
This is a total RNG fest. You could end up with all or no support in a wave and either get your team wiped or not able to do enough damage to keep up. Your ULT charge carries over with each "swap" so if you have a non-optimal character, save your ULT for the next 60 seconds in hopes it will be useful then. Team communication at each swap is key to knowing who will use which ults and when.
This is likely one of the two more difficult of the 6 challenges.
Here are the current spawn timers:8:00 Mission Start
6:51 Tire (Random)
6:33 Tire (Random)
5:48 The Reaper
4:54 Tire (Random)
4:39 Tire (Random)
4:25 Tire (Random)
3:53 Junkenstein's Monster
3:24 Tire (Random)
2:52 The Summoner
2:36 Tire (Right)
1:52 Dr. Junkenstein
1:36 The Reaper
0:49 Tire (Left)
0:47 Tire (Right)
0:33 The Reaper
0:25 Tire (Center)
0:00 The Witch, Dr. Junkenstein, Junkenstein's Monster
Last Boss Dies -> Victory
Things to note:- The time given is when the audio cue is initiated. There may be a few seconds before the enemy is fully spawned and able to be damaged.
- For the random tire spawns, listen for the call-outs by the heroes. They will say "ramparts" or "left" for a left spawn, "center" or "bridge" for a center spawn, or "right" for the right spawn.
I recommend the following team composition:Soldier: 76, + any 3 DPS.
The goal is to build as much ULT charge as possible before the first swap. Soldier: 76 is there in case some healing is needed in the initial minute.
This achievement stacks with and will unlock the following achievements if not previously earned:Upon completion, the hero you played will count as one of the heroes needed for progress toward this achievement: