If there was any perk in Killing Floor 2 that needs an explanation, it's the Survivalist. Released to commemorate KF2's departure from Early Access in 2016, the Survivalist remains shrouded in mystique to many players. The perk is a closer, an archetype to fill any remaining holes in the game's roster.
Having few unique abilities of its own, the Survivalist Skill-Tree takes mechanics from every other perk in the game- Allowing indecisive players to mix and match abilities, creating a completely unique class. The added freedom has its drawbacks: Survivalist cannot match or surpass the perks it mimics; I'd call it an understudy.
Due to the perk's open ended structure, there's no ultimately correct way to build Survivalist. Also for that reason, it's not a recommended role for newcomers, as you'll have to learn how to use every other perk first before combining them. If you don't know where to start, consider playing around with the Survivalist's unique weapon: The 'Freezethrower'.
This deadly cryogenic garden hose lays waste to small Zeds, and stops bigger ones cold. Leaning on the Freezethrower works well solo, but a real challenge comes when playing with others. Effectively playing Survivalist in team games could only be described as shapeshifting: Be ready to observe the flow of each round and modify your build accordingly. Remember, you're a Jack of ALL trades, not most. This perk shines when there's a lot of little things that need doing- Like a Maid, or Butler... With a gun.
Jokes aside, here's my personal Survivalist build. It's designed to ape other popular perks in Killing Floor, but has a flavor all its own. Feel free to change these skills around, that's the whole point of this role!
Be the Garbage Man you've always wanted to be- Deleting Clots, Crawlers, and Bloats with ease. Use the Freezethrower's primary attack to take out small fries, and the alternate fire to stun big Zeds for your buddies. Tactical Reload is a necessity, as you'll be using a Commando weapon to back up your Freezethrower.
I'd recommended choosing Melee Expert next as a utility, using the move speed bonus to retreat. Should things go South, switch to your Gore-Shiv and get out of there! Lording over the small Zeds means you'll burn through ammo quickly, so Ammo Vest is taken to keep you in the fight.
Spontaneous Zed-plosion is next, a skill that makes crowd control a breeze. I leave this last selection up to debate: Both Zed-Time skills are equally good for this role, and make the Freezethrower/Commando combo a joy to use. If your playing alone, strongly consider Madman, it'll multiply your damage per second and make short work of big targets. In a team, Lockdown reaches much the same result- Cover your Sharpshooter and give them easy picks by freezing Scrakes and Fleshpounds in their tracks.
The Survivalist experience resides on the poles: It can either be a complete washout, or a spectacular performance: Where every cog perfectly comes together to from an unstoppable Zed killing machine. The deciding factor is you - Now go play some KF.