I am currently near the end of we got hostiles and am carrying both the pizza box and purple hat with me. Before I go any further I just want to know if it is possible to get both achievements in one run or if I should just focus on the hat?

Hmm, pizza box can be found in Questionable Ethics chapter. I took both of them but stuck on Gargantua at the end of Surface Tension chapter.

Probably best to do a couple runs of the game. It's a great game to experience and there are a number of scenarios where the game will suddenly cut you off from backtracking. E.g., ladders breaking, debris crumbling over the path behind you, combat demanding too much of your attention, and moments where the hat can easily get stuck in some crack somewhere and never see the light of day ever again. Save yourself the mental strain and just take your time with all three achievements.

Well if someone wants us to give up it means there's hidden ending when both gadgets are at the end of game!

Vents in Interloper don't suck up items unless you are grabbing them I think, so those parts would be impossible, but even if you managed to somehow get both items through every vent, in the final jumppad with all the barrels going up the tower, you get captured in mid air by a blue forcefield, I don't know how it could be possible to carry both items in this part

Originally posted by Nacho:

Vents in Interloper don't suck up items unless you are grabbing them I think, so those parts would be impossible, but even if you managed to somehow get both items through every vent, in the final jumppad with all the barrels going up the tower, you get captured in mid air by a blue forcefield, I don't know how it could be possible to carry both items in this part

Yup, at one point the physics make this an impossible quest and I would rather prefer the developers not spending any time on "fixing" this unless they overwork the WHOLE game in a way that makes this endeavour less painful. Every chase sequence alone is a nightmare with both items.
Personally, I managed to get up to Gargantua's lair before saving and doing the rest of the game twice. Someone else managed to get deeper into Interloper.

So, no it is not possible

It's not possible to take both of them in the last part of Surface Tension at the Gargantua chase. Even if you set the difficulty to Normal, Gargantua will kill you before you get both things out of the tunnel. If anyone could do it please rep.

It is possible to get them both all the way to the last section of Interloper (another player did the same thing), but I had to give up there. I managed to launch both up to the top of that last jump pad area at roughly the same time, but couldn't manage to get them both into the blue forcefield box that carries you away.
The long vent right after that also seems impossible to get them both through even if you got them to it.
https://steamcommunity.com/sharedfiles/filedetails/?id=2025445056
https://steamcommunity.com/sharedfiles/filedetails/?id=2025443681
The pizza box is just visible to the upper left of the crosshair here, it either falls down past you as the forcefield appears or disappears into the black vents above you.

To get past Gargantua, just throw both items forward a bit, then go hide in the corner after the first ramp down. He'll retreat and I even managed to get him stuck so he didn't follow me at all through the rest of the tunnel. Then at one point in Xen I had to use a remote explosive to launch one item across a gap. Working on Gonarch's Lair now and still have both...

But don't worry, there's a THIRD item you're supposed to carry for some other achievements. It's a bit much if you ask me.

WAT? Which third item?!? OMG, here we go again :D

Originally posted by DzieX:

WAT? Which third item?!? OMG, here we go again :D

The Cyanogen canister found in the outpost. But it is far easier to transport since you can use a teleporter and skip the whole Gonarch's Lair for it. For MAGICAL REASONS though, the same teleporter can not teleport your other two items. Also, it actually provides an alternative route in the game, is helpful and interesting.

But getting all three items across the Xen gap is indeed annoying.

Ohh, I thought something else. That one I tookseveral times. It;s pity hat or pizza box can't be teleported to the end of the Gonarch map.

How do you get multiple items across the Xen gap?

Managed to get both hat & pizza through the Gargantua chase in Surface Tension. First I run carrying the hat, upon reaching the final door I threw the hat into a corner (just beyond the point that will cave in, you know), then run back and PAST the Gargantua (good to have full 100/100 health for this scene), picked up the pizza, run back with the pizza again passing Gargantua and taking damage, once at the final door again I threw the pizza off my hands, proceeded to the tower to kill the beast, then went back to the door he ripped apart and picked up the items.

Just made it to Xen with both items (indeed one can just throw them into the big portal before passing through himself). Now taking a few days break before carrying on. Wonder how far I can get without having to replay entire chapters/maps.

Originally posted by Anh Alexander:

How do you get multiple items across the Xen gap?

Which gap are you referring to? You have to grenade/satchel charge jump in a couple of places to grab the other item(s)

After some great effort, I managed to get the pizza and hat past the Gonarch chase before dropping some crystals on it. But now I have to drop down a deep pit. The problem is that there's a strong wind going up, and the items don't fall down. I can only get them down when holding them.