Mass Effect Andromeda Gameplay Trailer: 9 Things You Totally Missed
6. Those Enemies Are The Remnant
A quick summation of the leaked/assumed plot line is that this Andromeda Initiative team awake in the farthest reaches of deep space, begin exploring ancient artefacts like the Vaults seen in the new footage, but in the process awake an ancient force known as the Remnant.
Taken from the April 2015 leak: "After grabbing certain artefacts you want to take back home with you, the Raid's defences will activate; comprised of "traps" "defence robots" and sometimes a "change the architecture of the vault itself to stop you from escaping".
This matches up perfectly with what we saw, especially as if you listen close, Cora can be heard saying "More Remnant" when the creatures first appear. In addition, the 'changing architecture' is clearly the collapsible/transforming platforms, and the 'defences activating' must be what we see coming after the team in the closing seconds.
You can expect to explore a ton of these individually-designed Vaults in search of artefacts and information about the mysterious Andromeda galaxy - providing you can survive whatever gets triggered in the process.