iOS 12 - iOS 12.2 and 12.4 - Chimera Jailbreak
Chimera Jailbreak Guide
Download Chimera IPA
Download Cydia Impactor from here.
Connect your device with Computer and Launch Cydia impactor from the Computer.
It will detect your device and then drag the Chimera IPA on to Cydia Impactor.
Enter your Apple ID & Password when prompt. It will sideload the Chimera app to your device.
After, few seconds, Chimera app appeared on your device and trust the app before running it. Go to Settings --> General --> Profiles & Device Management --> Trust the app.
Now run the Chimera Jailbreak app from your device and Tap the Jailbreak button to begin the jailbreak process.