Transformers: Prime/Radar

Because they are robots, the animators were able to get by the fact that the Transformers actually "bleed" when damaged. "Helped" by the fact that the mooks always seem to arrive in high numbers and thus Megatron rarely finds himself running out.
- Almost all Vehicon mooks get horribly slaughtered in ways you wouldn't want to see for a human being.
Also, the way Jack runs his hands up and down Arcee's body while she's in vehicle mode would be very inappropriate under any other context. Not least because of Cool Big Sis. (Note that at the time, he didn't actually know she wasn't anything but a regular motorcycle).
At one point, Bulkhead makes a sly remark about how Agent Fowler "has some pretty big bearings... for a human."
In episode 1 we get this gem: Bulkhead "I thought there were 2?" Arcee "Haven't you heard? Humans multiply."
In Episode 3, Bulkhead rips out an Vehicon's heart/spark onscreen in slow motion. While a child watches.
In Episode 5, it is very much a blink-and-miss-it moment but when Soundwave is busy taking over the observatory, he is shown going passed a human soldier that is shown slumped against a wall, almost certainly dead by his hand.
And then there's Arcee adding a whole new layer to Bulkhead and Wheeljack's friendship with a single question: "So, who's the boyfriend?"
In "Convoy", Fowler holds a Mook over the side of a speeding Optimus. High speed chases and driving besides tree branches don't mix, kids. Througout the rest of the episode, multiple casualties amount, but this one stands out.
- Really? What about the Mook Arcee knocked off of one of the MECH cars? He goes flying screaming through the air and, judging from the angle of the shot (which carefully hides his impact behind the crashing car), lands in the path of a second car. That car hits the first, flips into the air, hits the road, and explodes. With people inside. One imagines Optimus doesn't entirely understand the concept of "minimal force."
- Also in "Convoy" we have the D.N.G.S.; a MacGuffin the Autobots and MECH are chasing throughout the episode. But "dingus" is also slang for a man's special parts in the American Mid-West.
In "Speed Metal"

Knock Out: (In response to Starscream's order to cease street racing) Buff this.

- Accompanied by a gesture that almost made it look like Knockout was giving Starscream the finger.
In episode 10 Knockout gives Optimus a wolf whistle while commenting on his paint job.
Also in "Speed Metal," Arcee says "Uh Jack, a lady's vital stats are her own business." She was talking about her engine stats and acceleration, but if you take it out of context...
Scrap!
In "Operation: Breakdown", Bulkhead had to have crushed and stomped on MECH soldiers when he stormed their base. Not to mention, Breakdown himself crushing cars and throwing one at a helicopter that explodes.
June got her heels on for Optimus.
In "Stronger, Faster" Ratchet essentially invents a steroid in the form of Synthetic Energon. He uses it on himself, with drastic results.
- Later in the episode, Ratchet, further under the influence of the stuff, actually hits on Arcee.

Ratchet *suggestively clicking*: How's it humming?
Arcee: Did he just--?
Bulkhead: Stronger, faster, studlier.

One Shall Fall almost defied Infant Immortality with Raf's near-death.
- During Optimus's and Megatron's fight, Optimus was beating Megatron so hard that dark energon was punched out of his face. And energon is the transformers equivalent to blood.
"You like playing with the big robots, don't you, little girl?". Starscream, you PERV!
- In-context, he was simply trying to frighten Miko (mainly to taunt Bulkhead), but his tone still made it sound... unsettling.
Let's not forget that Airachnid is quite the creeper when it comes to Jack.
Episode 24 has Agent Fowler storming into the Autobot base and gives us this doozy:

Agent Fowler: What have you learned, Prime? And you'd better not blow smoke up my-(notices June standing nearby) Er, oh, ahaha, Mrs. Darby, what a nice surprise!

"Orion Pax Part 1" gives us Sierra commenting "Your mom looks good in leather... on your bike."
- In the same episode, we get Starscream effectively gutting a Vehicon and Arcee punching another one's head off, with a slight energon spill and all.
- This exchange, too:

Arcee: Anything else you'd like to mention that we already know?
Bulkhead: Nothing I can say in front of the children!

- And this between Jack and Sierra:

Sierra: Hi, Jack.
Jack: Sierra!
Sierra: How come I never see you around?
Jack: What are you taking about? We have chemistry together.
Sierra: (gives Jack an interesting look)
Jack: (nervously rubbing his neck)...Uh, I meant class, chemistry class.

In "Operation Bumblebee, Part 1", Silas and his MECH mooks shock Bee into unconsciousness, and remove his Transformation Cog. In other words: organ theft for the kids to watch
- Even more fun, they do the exact same thing to Starscream, who thought he was MECH's ally, after they lose access to Bumblebee's at the end of Part 2.
Also from :Operation Bumblebee, Part 2": Knock Out, after having obtained a Cybertronian artifact, asks Megatron what it is. Megatron demonstrates that it's a shield generator by firing at him with no prior warning. After it narrowly works, Knock Out gives us the following line:

Knock Out: I think I leaked a little transmission fluid.

While we're at it, how about Breakdown's death in "Crossfire"?
- One gets the impression it was only allowed because they chose to play Bloodless Carnage straight on that occasion. This was not the case with Airachnid, Megatron, the Insecticon and Starscream, who all bled a lot from what should have been minor wounds.
Silas' Disney Death is not one to take lightly either. He's crushed underneath Nemesis Prime's body and debris, ONSCREEN.
- Worse yet, some of his injuries are quite visible while he's on the operating table later; most of this body is covered, but you can clearly see that his face is horrifically bruised and mutilated.
- In the same episode, Nemesis Prime stabs Optimus in the stomach.
Airachnid, at Arcee's mercy, telling Arcee to make it hurt when Arcee kills her seems to suggest that in addition to being a confirmed sadist, she might also be a bit of a masochist too.
- Bulkhead beats a Starscream clone to death. We don't see the end results, due to it flashing to white with every blow that lands, but it's still implied to be horribly brutal.
In the episode Toxicity we're introduced to tox-en, a toxic form of energon, which Megatron used back in Cybertron as a mass destruction contagion-type weapon, very akin to a nuclear bomb, especially when we're shown a transformer get onscreen infected with the stuff (result being blisters and then death) and the fact that just being around the stuff unconstrained is hazardous. So yeah, radiation poisoning for kids.