Light in the Tunnel is the second Quest in Act 5 Chapter 3: The Struggle, and was released on September 6, 2017. This Quest promotes the use of Tech 
Champions and reduces the Attack Rating of Champions from all other Classes.
It contains 5 paths and ranges from 4 to 16 Opponents per path. There are 3 gates requiring Cosmic, Tech and Mutant Class Keys. A Tech and Mutant Class Key can be found as Path Rewards, while a Cosmic Class Key can be obtained by completing the Quest.
It is preceded by 5.3.1: Game Begins Anew and succeeded by 5.3.3: Dire Warning.
Nodes[]
Global 
[]
| Name | Effect(s) |
|---|---|
| Overclocked | All Champion classes but Tech reduce their Base Attack by 50%. |
| Champion Boost | +300% Attack & Health |
| Iso-Infused | +50% Attack and Health |
| WARNING | A third Special Attack has been activated! |
Dialogue[]
Doctor Voodoo: Thank you for your help, Summoner. I will stand with you while Strange does his clandestine work. Doctor Voodoo: It seems this is where the technology-focused Champions have been sequestered. Doctor Voodoo: Perhaps we can recruit more Champions to our cause. Surely they have seen the dangers of the Grandmaster's ways already.
- Transmission #1 - Upon entering the Quest
Rocket Raccoon: Summoner! You ain't here to beat the crap outta me, are you? No? Good. Rocket Raccoon: I need help from you 'n your pals! They split me and Groot up, it's awful! Rocket Raccoon: This Grandmaster guy's even worse than the Collector. He just puts people into statues instead 'a crystals! Rocket Raccoon: It's all the same, just worse! We gotta stop 'im!
- Transmission #2
Doctor Strange: Summoner, Jericho! I have news! Doctor Voodoo: Good news, I hope? Doctor Strange: I'm... not quite sure yet. We have found some curious crystalline splinters; different from the Collector's. They seem to attract one another, and radiate a dormant power. Doctor Strange: They might be a key to stopping the Grandmaster, but we'll need more time to research.
Civil Warrior: Don't worry, Doctors. We can buy you that time. Doctor Voodoo: Civil Warrior! You're a sight for sore eyes!
- Transmission #3
Civil Warrior: I trust Strange's hunch. You, Voodoo, and I can keep the Grandmaster's "game" going, while he works in secret. Civil Warrior: I just hope it will be enough time.
The Grandmaster: What's this? The Summoner and the good Captain, sharing a private whisper? That simply won't do! The Grandmaster: There are fights to be had, my Champions! Now, do what you were brought here to do!
Howard the Duck: LEMME AT 'EM, LEMME AT 'EM!
- Transmission #4 - Before fighting Howard the Duck