Welcome to my collection of proved tips and tricks. At least they were tested in U31 and some were re-tested in U32.
Axes and drills are sources of "melee" damage type so they can cause "vampire" perk procks. In the game there are a lot of different damage types, but only the "melee" one affects the perk.
Note: I have experienced axekills not giving me +5 hp, I guess it is connected with fact axes' damage is not 100% melee.
Since *one of the patches* hitting electrocuting crystalls with axes does not cause damage to you. It opens a very tasty exploit. You can throw 3 axes into a crystal and it gets destroyed. And your axes behave like "missed" so they are available for retrieval. The top 1 way to fight electrocrystals. Quick, no ammo and health expences.
In the swamp biome you can throw axes along the fields of mushrooms, emmiting toxic spores. The mushrooms that were close enough to the axe get destroyed but the axe is treated as a "missed" one (if it hits the ground, not a random swarmer passing by xD). Once again, quick and no ammo usage. The fly-by damage seems to affect most things in the game but not swarmers and jellies. I have no explanation for such behaviour.
On impact, axes deal some damage and cast strong short stun within a small radius. (Strong stun = stuns every enemy that is not immune to it). It can save you from being whalepiped with a dense pack of macteras or *STFU* the preatorian that is going to cover a defence point with its vomit.
The tips of cave leaches' tentacles can recieve damage. You can thus you can fear it away hitting the tip, not the body. If a leach is asking for *docking permission*, you can defend yourself with power drills. GIT GUD level: kill leaches with pickaxe's power attacks.
Ebonust are a piece of cake for a driller. Use drills to open them in a moment for little fuel. Or throw an axe in it. The axe is reusable in this case but it takes some time for aiming and picking the axe up.
Grabbers put om fire can skip their next approach. If it starts the approach too early, it can achieve "landing denial damage threshold" from the damage over time.
Now the flammer and its "Rate of Fire". Particulary why you would like it to be as LOW as possible. Sticky fuel pools distribution on time does not depend on the RoF. This means, the less the RoF is, the MOAR BURNING FLOOR you can make with the same amount of used ammo. The same goes for heat radiance mod in T5. This makes the yellow flame reach OC being actually clean for sticky fuel and ammo builds.
Cryocannon "Ice Spear" OC can be used to hit frozen opressors. The idea is you need to start charging half a second before the opressor gets finally frozen with the ice left on the ground. If you have started the spear chargin process but see there is no more point in shooting it now, switch weapon to save the ammo.
If you have put a bug on fire in Glacial Strata, it can get thermal shock from environment. Either cold air flows or... warm oasises. Yep, the bug is on fire and it gets T-shocked with a warm spring.
The "Thin Containment Field" T5 EPC mod (TCF for short) can be used for massive AoE or "remote mining". If the charged shot gets hit by any source of kinetic damage type, it collapses with amazing results. Kinetic damage is caused by all the guns but PGL, BC, flammer and cryo. The case is you trigger the TCF proc with a properly timed regular EPC shot. Be careful while mining eggs. The spiky organics tends to intercept the charged shot hitboxes and cause regular charged shot explosion. And I do not approve of mining scouts with TCF... TCF can also be used to get down your teammates killed on platforms or thin floors if going up there is not a good option.
C4 can be not only a teamkiller tool, it can actually save the nearby teammates. With the stun upgrade you can explode it and get an area safe for a few seconds. Be it a teammate revival, resupplying or just a retreat, you will have the time you need. Its stun is "strong", 100% chance to stun all the stunable enemies, even swarmers xD. Just make sure the dwarf you are going to save is not within the "haha now you die" radius.
The "Hoverclock" M1K OC can be only "used" once before returning to the ground. Another tip: when you start charging the shot, it takes your velocity. And gives it back when you shoot the shot or keep aiming for a second. If you do not shot and switch a weapon within a second, you fool the system and don't get the velocity back. It lets you use this OC in the same way as the "Hover Boots" perk.
Some rocket science. If you want to fly as long or as hign as possible with help of your "Special Powder" boomstick OC, make the two shots as quick as possible, and the RoF (not the one reloading) mod will help you a lot in such a case. The idea is about your max height and distance grow as starting_speed^2.
The IFG nade increases by 1.3 damage recieved by the affected enemies. And this is not a T5 Zhukov Paired mod (which will result into 1.3*1.3 = 1.69), it is the built-in IFG feature that affects all the weapons. Interaction with environmental damage and damage over time is not tested by me though.
The explosion mod in T5 of Breach Cutter is broken. If you do not trigger the explosion on your own, your BC will not shoot for a few seconds.
The 32 Update has buffed "Hyperpropellant" PGL OC. Now it changes grenade's impact damage type to "disintergration". Since then bulks, dreads and opressors don't have resistance to it. It also makes preatorians killed by this HP PGL direct hit DO NOT cast a cloud of toxic gases/emmit radiation/freeze the area.
"Big Bertha" Auto-Cannon OC decreases max RoF to initial RoF. It casues bugs in full RoF damage bonus mod making it not to trigger. Use max RoF mods to make max RoF damage bonus mod not useless on BB AC.
Korlok sprouts do not shoot while being damaged. Neurotox and flaming DoTs have short enough time intervals to disable it. Korlok's healing bulb work can't be interrupted even by freezing it.
Pickaxes ignore opressor's armor. Feel free to smash its face with power attack. Make sure you don't get kicked few kilometres away.
Shots of Glyphids AcidSpitters and Menaces intercept your projectiles, axes too!
Bulk detonator, opressor and dread's yellow health have resistance for explosive damage. Usually there is no point in using "explosion" damage type sources agains them.
Vampire is an extremelly powerful perk, especially in builds made "for it". Disagree? Take cryocannon, cold radiance, freeze a pack of grunts and see it on your own. It also lets you avoid dying again after "Iron Will" perk effect times out if you have no resuplies or redsugar to use. Unfortunatelly, IW is a bit bugged and can kill you on timeout whether you got some health ore not.
"CYA in Hell" active ability casts an area of absolute fear that makes bulks and dreads run away. WARNING: this does not save you from shots and random Q'Ronnars. The perk has both charges and cooldown but can only be used once between deaths.
Dark Morkite and Pots of Gold beer only affect mining with your pickaxe. Explosion and BOSCO mining reults are not buffed.
The "Dash" perk says you ignore slowdowns while it is active. The punchline is slasher's effect affect your dashing speed. It is either a GSG's mistake in description, or slasher's effect is not treated as a slowdown. Either way, the devs should make it more clear in the perk's description.
Instead of trying to catch the timing or spamming "E" button you can simply hold it pressed while falling on a zipline. If there is at least a single moment when you can grab it, you will do it. Same goes for liquid morkite pipelines.
After and ancient bug of armour plates mechanics got fixed, shots that destroy a plate are not affected with its penalties. It lets armour damage mods affect breakpoints even in the case you try to oneshot your targest. The weapon that got the most buff from it is PGL HP. Now it can casue full damage to preatorians and shellbacks in 99% of direct impacts. According to my exoerience it can fail casting full damage if it impacts at such an angle that it hits another plate after destroying the first one.
Dreadnought's red health bar is often called "armour". But it is not affected with "armour plates mechanics", armour damage bonuses and so on. The only difference from yellow health is that it is not a critspot and weapon's crit bonuses are not applied.