ANSWER:
Please note that some items (included in your Pixel Pack) are available in the Battle HQ only after reaching Chapter 3 of Ancient Garden.
Pixel Pack*: Includes 8 primary weapons - One per available Hero.
THE FRAGMENTER: MARIO

ASCII ERADICATOR: RABBID LUIGI

RETRO DEFLATOR: RABBID PEACH

BOOM BROOM: LUIGI

CARTRIDGE COMMANDER: RABBID MARIO

BAIT N' SWITCH BRUISER: PEACH

RASTER BLASTER: RABBID YOSHI

HOSTILE VOXEL: YOSHI

CRANIAL ABOGATOR: MARIO

EFFECTUAL ATOMIZER: RABBID LUIGI

CALAMITOUS COUPE: RABBID PEACH

JEOPARDOUS JALOPY: LUIGI

BALEFUL BAD-ENDER: RABBID MARIO

DEFALCATING DANDY: PEACH

EXALTED ENTROPIC EGGS: RABBID YOSHI

DIRELY DULCET DOOMSAYER: YOSHI

Ultra Challenge Pack
- 8 new ultra-hard challenges inside each world’s Secret chapter
- 5 exclusive co-op maps
- Gather your heroes and dive into eight new Ultra Hard Challenges to prove your worth! In addition, a gust of chaos brings frenzy to the co-op mode; Chain Chomps, Tornados, Boos, and Pyroclasts have become unstoppable and are wreaking havoc on the 5 exclusive new co-op maps.
- Get ready to team up against their chaotic forces in the brand new Cataclysm Kerfuffle Co-op Campaign!
New story content:
Swing into a new journey in Mario + Rabbids Kingdom Battle: Donkey Kong Adventure!
Embark in an epic battle against a vengeful Rabbid Kong who uses his new powers to take over a mysterious island. Donkey Kong, Rabbid Peach, and a moody new Rabbid hero, Rabbid Cranky, will team up on a journey across four brand-new environments. Discover a world full of reinvented tactical gameplay, new enemies, and secrets to uncover.
Released on June 26, 2018

Stay tuned for any updates!
For information on how to find your content in-game, check out this FAQ HERE.
Finally, if you would like to know more about sharing content on Nintendo Switch, feel free to visit this article HERE.
*The Pixel Pack and the Steampunk Pack are not available as a standalone for now. We will update players if they become available at a later date.