Kerbal Space Program (v1.12.5.03190) [gog] -

: To reach the outer planets (Jool, Eeloo) with minimal fuel, launch toward Eve first. Passing behind Eve in its orbit will "pull" your craft, boosting your velocity and raising your apoapsis significantly for almost zero delta-V.

If you’d like, I can give you a (like Duna or Laythe) or help you troubleshoot a specific craft design that keeps flipping! Kerbal Space Program (v1.12.5.03190) [GOG]

: Completely transforms the ground textures into high-detail, lush environments. : To reach the outer planets (Jool, Eeloo)

The most interesting physics quirk in KSP is that your engines are more effective when you are moving fast. Eeloo) with minimal fuel