Butterscotch Shenanigans has updated Crashlands such that all of these achievements are no longer needed. Each of the missions will appear in Crashlands by default. This was done potentially due to the controversial nature of making people play their other games.

Still, the achievements in each of the games still exist, so it is still possible to earn these achievements; they just don't influence Crashlands content.

(Thanks to katacks+ and jeepjumping_jonah for pointing this out.)

Towelfight 2, Roid Rage, Flop Rocket, and Quadropus Rampage are all free downloads for iOS and Android, but each is really a premium game and offers a "butter-up" that is a one-time purchase. To unlock the perks, butter-ups are not strictly necessary, except for Flop Rocket, but will help for a better experience and support the studio. Buttering-up all the games - which I recommend - will cost a total of ~$11, or you can just butter-up Flop Rocket for ~$3 if you're cheap.

Also, I highly recommend, if possible, playing on a larger screen/tablet. These games are all served well by a larger screen.

It's recommended that you complete each of the perks in the order presented by this guide, as, generally, there are some perks and side-perks (ones we won't be going over in this guide) in the preceding games that you might complete in the process that will help you and give you a boost in the succeeding games (incidentally the games were all released in this order).

Make sure that you're logged into the same Bscotch ID in the games to save your perks!

Downloads: on the App Store[apps.apple.com] and on the Google Play store[play.google.com]

Butter-up: $2.99 (not required)

How to get the perk: To get the Marsh Madness perk, you have to beat Luhmpz in the Purple Marsh of Death. This is just part of the main story of the game, so just play until you reach Luhmpz, who is the last boss of the second area, and defeat him. Playing casually, this will take anywhere from 1.5 to 2.5 hours of gameplay.

Crashlands mission unlock: Talk to Umaa in the Bawg at Ooxinax to initiate the quest, "a secret...sidequest to discover the remnants of Luhmpz's reign..." Through doing the quest, you'll get The Bubbler, a powerful trinket that causes bubbles to spawn that help you by suicide-bombing your enemies.

Downloads: on the App Store[apps.apple.com] and on the Google Play store[play.google.com]

Butter-up: $2.99 (not required)

How to get the perk: This one is perhaps the easiest and with the least time investment involved. To get the Tack Jones perk, you have to hold 4 simultaneous artifacts. Artifacts are glowing items with passive abilities that you can find on the ground or buy from Grubby when he appears; picking one up adds its icon to the right side of the screen. Now just pick up 4 of them in a run. That's it!

Crashlands mission unlock: Talk to Brikabrack to initiate the quest, "Tack's secret Savanna sidequest..." Through doing the quest, you'll get the Smash Racket, a powerful gadget that makes you leap into the air and smash the ground.

Downloads: on the App Store[apps.apple.com] and on the Google Play store[play.google.com]

Butter-up: $2.99 (required)

How to get the perk: OK, this one's a real grind. To get the Rockin' It perk, you need to fully upgrade your Flop Rocket. The reason you need a butter-up for this one is that buttering-up unlocks 8 more research paths (for a total of 12 research paths), and you need to fully upgrade each path to get the perk. This means collecting a total of 244,800 coins - yikes! I nearly went insane saving up the coins. On the way, I even made it to space three times, once as a potato. Even after all that I had to grind for another hour one evening to get the last upgrades. They should really rebalance this one. But it was worth it for what you get...

Crashlands mission unlock: Talk to Will (and Brad) in the Tundra to initiate the quest. You'll need to hunt down Gigantigax the Gulanti, who is a random encounter anywhere in the Tundra (but to find him it might help to go further out?) Through doing the quest, you'll get the Juicejockey Vacuhelm, a piece of legendary armor that is the strongest helm in the game. It's also a bit scary looking.

Downloads: on the App Store[apps.apple.com] and on the Google Play store[play.google.com] (Note: the title is Roid Rampage on the app store.)

Butter-up: $1.99 (not required)

How to get the perk: Before you can get the perk in Roid Rage, there is a prerequisite that you have to fill by playing Towelfight 2. You have to beat Forn, the final boss in Towelfight 2, to get the Those Lasers perk (this may take ~3-3.5 hours of gameplay in Towelfight 2).

Once you have Those Lasers, you're ready to play Roid Rage: in Roid Rage every 10 juice you collect will cause a laser light show (it doesn't matter which ship or character you use). The juice until the next light show is displayed in the lower left of the screen. The Flavor Laser perk requires that you throw 3 light shows, so that means you have to collect 30 juice in one run.

This game can be difficult, but it's a worthy challenge. I recommend the Goldinox ship and the Unpaid Intern character, as they fly the slowest, and to always fly generally in the northward direction to avoid your controls being inverted. Also, don't feel like you have to go after every juice you see; just keep flying until you run into an easier-to-reach one.

Crashlands mission unlock: Talk to Ziztik in the Bawg at Ziztik's Shrine to initiate the quest, "a secret Bawg sidequest to uncover the fate of a Juice Jockey Intern..." Through doing the quest, you'll get The Orb of Forn, a powerful gadget that makes a trio of lasers appear and rotate around you.

https://www.reddit.com/r/crashlands/comments/3wwz1u/request_guide_to_unlock_all_perks_by_playing/
https://www.reddit.com/r/crashlands/comments/5q7nzo/to_those_who_are_confused_about_the_tack_jones/
https://forums.bscotch.net/viewtopic.php?f=71&t=4364
https://forums.bscotch.net/viewtopic.php?f=51&t=4614

Hopefully this guide helped you! This is my first guide. Do you have any questions or comments? Did you notice any mistakes in the guide or do you have any suggestions? Are there any figures/illustrations that would make this guide better? Please leave them below!