What thing feels the best to do in KSP?

[pasukaru76]

First Mun landing, first succesful interplanetary mission, making orbit at Moho, seeing your periapse rise out of the atmosphere at Eve.

And, oddly, successfully managing to launch non-aerodynamic monstrosities into LKO.

[spacebrick3]

Every time I achieve something new, like for Mun landings, docking, and creating a successful SSTO. Next up is probably asteroid catching.

[Jeb1969]

Watching things blow up, because nothing screams what a major rush in Kerbal Space Program than having your spacecraft unexpectedly detonate in flight. That or doing a successful re-entry burn with RCS only because you foolishly drained the re-entry tanks in a desperate attempt for a periapsis above the seventy thousand metre mark. 

Edited May 29, 2016 by Jeb1969
I don't know

[Xyphos]

Getting your VTOLs to work properly, but the amount of RCS ports needed for that is more part-count then the vessel itself.

[MircoMars]

I've played KSP for quite a while, so I learned intercepting and docking when this was still new. after rodeo-dockings with shaky, unbalanced ships or no RCS dockings I'm more exhausted and relieved than anything else. I think my first mun landing was on winglets... I faintly remember how thrilling that was for the first few dozen times. It still is in situations of near catastrophe or landing on mean slopes or so.

what reliably leaves a feeling of greatness is landing a capsule close to KSC. most of the times I land in the ocean or the grasslands, but when my Kerbals could walk home from the landing site, I feel kinda proud.

[Kristobal]

Most satisfying thing I ever did was rescue a kerbal from Munar orbit that had zero EVA propellant left. Nothing quite like flying right up to within inches of a kerbal and rotating your ship juuust right 

[TheRag]

Me? I love to land on Duna from time to time. I usually design giant missions that require multiple space stations and a Duna base for those tiny green men to reach. Requires days to weeks to plan, but usually satisfy my KSP demand for a while.

 

Second thing is landing any small lander on Laythe, without excessive Dv and watching the days past.

[Tiberius K]

Dream ... Build ... Fly

It was after seeing this video that I was finally "right, that's it.  I'm doing what it takes to get this game".  I showed my wife the video and she (thankfully) understood so we broke into our saving and I built a PC.

For me the real joy is in the process of dreaming and building.  I spend a LONG time in the VAB tweaking, balancing thrust, positioning experiments/batteries/solar panels/landing legs just so, solving all the design problems that arise until it's something I'm truly proud of.  When the fairings detach, the solar panels open and I line up my burn I feel a real sense of achievement

I really enjoy the flying part, it's the icing on the cake, but for me the dream/build is what set's this game apart from anything else I've ever played

[Van Disaster]

1 hour ago, Kristobal said:

Most satisfying thing I ever did was rescue a kerbal from Munar orbit that had zero EVA propellant left. Nothing quite like flying right up to within inches of a kerbal and rotating your ship juuust right 

I think most people enjoy recovering from their unexpected mishaps at least as much as the original mission I certainly always loved rescue missions ( unless they're lifesupport-running-out missions ). For amusement stick a KAS winch to part of the ship, EVA a kerbal & use them to take the end of the winch to your rescuee, and then just throw the ship around a bit...

Spoiler

 

Sadly these days I don't seem to need anything like the same number of rescue missions.

[KerikBalm]

Its hard to choose between the following 3:

* Setting down one another world... but it the Mun, Duna, Eve, laythe, etc. An "the Eagle has landed" moment is great

* Setting down on Kerbin again, particularly with a spaceplane, or (and this happens much less often) setting down in the water near KSC, within view of the buildings (most recently for me, it was a 97.5% recovery bonus, considering KSC itself is 98%... it was very close). The "there and back again"/ "home again" feeling... but anywhere on kerbin works.... even if its a pod coming in hot from a return from Moho, landing in Kerbin's badlands... back on the ground with a bright blue sky overhead is great.

* A successful rendevous and docking... particularly assembling a spacestation/interplanetary vessel, or docking a lander/ferry (not neccessarily STS shuttle, just the ferry to get stuff to the station) with it

[Brainlord Mesomorph]

To crush your enemies. See them driven before you. Hear the lamentations of their women. 

 

/ wait wrong game. 

Edited May 30, 2016 by Brainlord Mesomorph

[SpacedCowboy]

To complete a mission without the game crashing.