I have played 7 nations in all of my experience and I can confidently list out top toxic tanks in Ground RB mid tier.
KV-1B/E: br 4.0
Toxic armour of about 100mm all round at a low br, crazy angle normalisation round, decent mobility able to keep up with panzer 4.
Can go to 4.3+
VIDAR:
We all have been laser range found and sniped from the other side of the map with this 60+mm pen HE launcher with thermal sites, so no hiding from it. 900m/s Velocity also makes it very viable. Large tin can can absorb lots of punishment due to shells overpenning.
Can go to 8.7+
Turm III:
Great mobility, gun handling, auto loader of 5s, coax 30mm and spalling in hull gets absorbed by ball turret.
Can go to 8.7+
U-SH 405:
Rocket HEAT spam, decent mobility on road. Toxicity potential is very high, but generally able to deal with. It can stay at its current br.
SAV20.12.48:
120mm 1.2s auto loader, 80+mm pen, good mobility , and the 120mm shell has 890g of TNT!
Just not at 3.7 br, I am not sure where it will be balanced.
Raketenautomat:
Basically U-SH 405 but a bit less annoying. Still quite annoying though.
Depends on one’s definition of “toxic.” I usually group toxic and “rat like” tanks together. As I’ve only played the USA (and refuse to main any others, fight me) I can list at least a few that are a bit rat like:
T114: High mobility, recoilless gun with a high pen HEAT round, and small enough to almost completely hide with bushes.
M56 Scorpion: Most of the same reasons as above, but now with APHE and an extra crew member.
Hellcats: Depending how you play these, they can be super ratty, especially after the horsepower increase. Super Hellcat is my favorite tier-for-tier.
One I don’t particularly agree or disagree with but see a lot of hate towards: HSTVL. A lot of people think this thing is toxic for its high reload rate and virtually crewless turret. But for that, I raise it to:
2S38: I mean does anything really need to be said about this that hasn’t already? Lots of people love this thing and lots more hate it. Rapid fire rate, gen 2/3 thermals, crewless turret, proxy HE round, APHE at top tier (which can be devastating if you know how to use a light tank properly).
Down at the lower BRs, the Stuart series are fairly ratty due to having low speed stabilizers and a high fire rate. I would also group the BT-5/7’s in here too as APHE at that low of a BR is just a one shot kill for almost anything it sees.
Probably more, I might come back and edit this if I can think of anything else.
After some time I started playing with the Br4.0 again, specifically with the Churchill NA75 and the concept 3. What I found toxic would be the T-34, it seems that the hull armor was modified. When I used them Tanks didn’t seem bad to me, with a bullet with 60° penetration a little absurd but with decent armor as long as you were careful since a pz4 with the 75mm cannon could kill you easily, however now I have realized that the devs They have touched something, since with the cannon of the concept 3 I have not yet been able to pierce the front of a T-34, and that penetrates more than the cannon of the pz4, apart from that the T-34 1942 has the 75mm door that It should hold much less than those 75mm.
77hv on the concept I hate, it’s so in accurate but for the penetration just shoot the turret neck or the mantlet. Won’t have random bounce issues due to angle anymore.
Of course, but at more than 300 meters you already have to pray that you give it that extremely small space, and if you add that to the fact that it is a full AP and there are times that it only kills one crew member, it doesn’t usually end well. On the other hand On the other hand, I see that the concept 3 has had an extremely soft suspension, so when braking it is very difficult to stabilize the barrel.