Soulframe tips and basic info
enemy levels vary across the open world, with some areas always having higher levels and some always having lower levels, so keep an eye on the levels of enemies you engage and be ready to run away if they turn out to be too tough
the open-world versions of bosses that are in the story quests see to be harder than their story counterparts (e.g. the Vadagar Bear vs. Bromius); I assume this is a recent change to make the story quests more accessible (thankfully)
when a weapon drops from an enemy, you can either take it into your inventory by pressing F, or immediately dismantle it by holding F. if it's white quality (i.e. not green, blue, purple, or gold) or is low quality and has no icons under "Tempers" in its tooltip, dismantle it
though you can look at your inventory any time, you can't dismantle weapons outside the Nightfold
it's easier to find duplicate weapons in your inventory if you go to its weapons tab and Sort Name
there's no death penalty, other than having to fly back to your body from the nearest respawn stone thing; enemy HP doesn't even reset while you're away, unless they're Ode and they have one of those white-clothed healers they sometimes have
if you see an Ode wearing white, kill them first. if you see two of them in a group, you're gonna have a hard time! just focus on one first and try to kill them faster than the other one can heal them
there are stumps with little broken statues on them. you can only interact with them from a certain angle, so circle close around them until you find the interact prompt
dungeons you go through some kind of door to enter, like Dermak Undercity and Glades of Andurin, are different every time: like Warframe's mission nodes, they're procedurally cobbled together from a set of "tiles" with various structures and entrances, then populated with loot, enemies, and puzzles
you can get a little money and sometimes some basic materials by destroying barrels, crates, some broken crates, some jars and pots, some baskets, a certain type of shelf, and certain small carts
(crates and barrels that look reinforced are not destructible)
you can middle-click while holding right-click to throw your melee weapon, then right+middle-click again to recall it; this is also used to interact with some puzzles if you don't have a ranged weapon on you
if you discover you've been mysteriously disarmed, your melee weapon missing, it's because you threw it and forgot to recall it
(you don't have to return to where you threw it, you can recall it from any distance)
when not holding right-click, middle-click does a heavy attack
the blue glowing thing with cargo hanging from it can be shot to drop the cargo on the ground as loot
you can't hit animals or civilians accidentally or on purpose (except for Ode hounds, but they flee unharmed as soon as you break their armor)
things you pick up in the open world may not be immediately visible in your inventory, they're officially added to it when you go to your Nightfold by holding the Tab key, when you leave a dungeon, when you complete a faction "votive" (minor quest), or when you log out (this is a holdover from Warframe's mission architecture, and a way to reduce the network traffic you and the servers have to handle)
you can press F on weapon racks that are visibly not empty and receive materials or possibly a weapon
if there's a piece of loot on the ground that isn't getting picked up when you walk over it, it's because it's a special item you can only hold like 50 of at a time
(all those special items limited to 50 can be turned in to your faction for standing! don't be letting them reach 50!)
the most important option in the skill tree of any pact, IMO, is the one that increases how many healing potions you can hold (from a minimum of 5 to a maximum of 7)
if you see any gold-glowing wisp-thingies in the open world, you can absorb them by holding Q and left-clicking, which reveals part of the name of the location you're at and unlocks a lore codex entry
(according to Reddit, you can tell whether any of these are currently in an area by seeing a black mote playing around the briefly-displayed location name as you enter the area; no mote, no wisp-thingy to be found)
you have a small chance to "Smite" enemies when hitting them, which causes a red, blue, or green wisp-thing to appear next to them that you can absorb the same way. smite does very little on its own, but many totems (weapon mods) and weapon skill tree nodes add functions to it, like AoE blind or self-healing, and/or can substantially increase the chance of it happening
there's a certain enemy that looks like a tall, weird mummy or zombie, with a white glow down the center of its body, that you have to absorb by holding Q and left-clicking within a few seconds after you kill it, or it'll revive (it's called a Deadwood Mockery)
holding Q and left-clicking in the general direction of an animal, when you're close enough, forces that animal to stop and listen to a little music performance by you, after which you'll receive a "totem" from it, which can be applied to certain types of weapons to add/enhance features of that weapon
(you can't do that to the same animal twice, nor to animals you've just freed from a cage)
just holding Q highlights loot, interactable objects, and nearby animals, reveals ghosts under certain circumstances, and makes you look cool based on your active pact (e.g. it temporarily gives you glowing antlers if you're using Garren Rood)
leveling up weapons and pacts levels up your character/account, which is a motivation to master lots of different weapons and pacts (but afaik there currently aren't many things that require a certain character/account level, if any)
the big, metal, head-like machines that pour sludge out of their mouths are called Ode'n Moaners, and you can destroy them by shooting and destroying both of the smaller faces that are located where their eyes would be. you get nothing for doing this, it's just very satisfying (actually you do get xp for it)
(Moaner face HP scales with the local level, which can make them very slow to destroy in some places)
if you jump or fall and hold right-click while attacking, your fall slows
magic weapons like Odiac have a skill tree node that can make their projectiles homing: