Quick answer
Complete four key tasks: confirm the cave is built by Covenant, hack their unencrypted battle net for tactical data, monitor enemy chatter via Master Chief's transcom system, shut down security with a holo panel, and destroy Halo using intact fusion reactors at Bottom's crash site.
Guide briefing
Halo Campaign Evolved Lore Have Mercy Achievement Guide
Complete four key tasks: confirm the cave is built by Covenant, hack their unencrypted battle net for tactical data, monitor enemy chatter via Master Chief's transcom system, shut down security with a holo panel, and destroy Halo using intact fusion reactors at Bottom's crash site.
Applies to
- — Halo Campaign Evolved
- — Lore Have Mercy achievement
- — Mission: Have Mercy and Halo

Target
Covenant battle net tactical data broadcast
- Checkpoint
- Inside the cave with non-natural formation
- Landmark
- The cave entrance (non-natural, built by Covenant)
Do this
- 1Enter the cave and confirm it is not a natural formation, as indicated by the dialogue at 43.92s.
- 2Hack into the Covenant battle net to intercept unencrypted tactical data broadcasts, as referenced at 51.08s–55.44s.
Confirmation
Covenant battle net tactical data broadcast is available as described. The cave leads to a location where Covenant tactical data is being broadcast; this is critical for completing the 'Have Mercy' achievement.

Target
enemy chatter monitoring via Master Chief's transcom system
- Checkpoint
- Spartan-117 and Cortana establish transcom link to intercept enemy communications
- Landmark
- Transcom system interface within Master Chief's suit
Do this
- 1Activate the Master Chief's suit's transcom system as instructed by Cortana.
- 2Monitor enemy chatter through the transcom feed to identify defensive system weaknesses.
Confirmation
enemy chatter monitoring via Master Chief's transcom system is available as described. Cortana explicitly states that analyzing enemy chatter will reveal defensive system vulnerabilities, which is essential for completing the 'Have Mercy' achievement.

Target
shut down the security system
- Checkpoint
- holo panel interaction
- Landmark
- holo panel
Do this
- 1Approach the holo panel located in the area where enemies are engaging.
- 2Interact with the holo panel to shut down the security system as instructed.
Confirmation
shut down the security system is available as described. The holo panel must be used before enemy reinforcements arrive; timing is critical to avoid being overwhelmed.

Target
Destroy Halo using the ship's fusion reactors
- Checkpoint
- Bottom's crash site
- Landmark
- Ship's fusion reactors at Bottom's crash site
Do this
- 1Navigate to Bottom's crash site as indicated in the transcript.
- 2Locate and interact with the ship's fusion reactors, which are described as relatively intact, to initiate the destruction sequence of Halo.
Confirmation
Destroy Halo using the ship's fusion reactors is available as described. The achievement 'Have Mercy' requires successfully triggering Halo's destruction via the fusion reactors. The transcript explicitly states that if the reactors are intact, they can be used to destroy Halo.