Rating: T for some violence and Cybertronian swearing

Warnings for this chapter: Synth-en effects and nasty injuries.

Summary: Ratchet does steroids, part 3.

Pairing(s): None.

Disclaimer: I don't own anything except Echo.

A/N: Look at that…I finally managed to update this! After another six months…*blushes and hides* Anyway, I've had this chapter planned since the beginning of the story, and I really liked how it turned out. The ending isn't great, but at least it's an ending.

Chapter 37: Side Effects

Echo stepped out of the groundbridge into the heat of the Utah sun, less than twenty yards from a vicious argument. Her optics widened and renewed concern caught in her vocalizer at the sound of her father's uncharacteristically raised voice. "…have no problem endangering us! Just ask Cliffjumper. Oh, wait, I forgot. He couldn't be here today!"

"What? Dad!" Echo raised her voice over Arcee and Bulkhead's angry retorts, running the few yards to the group of Autobots. "What is wrong with you?" When he didn't acknowledge her, she reached up and tugged on his shoulder. "Dad, you have to listen to me! That synth-en is getting to your processor. You have to come back to base, so we can –"

Ratchet shook her off roughly, ignoring her protest. "You know your problem, Optimus? For such a big, strong 'bot, you're soft. You didn't pound Megatron into scrap when you had the chance – many chances, in fact! And look what it's cost us! Look at the lives that have been taken because you couldn't – "

"Dad! STOP IT!" Echo screamed at the top of her vocalizer and grabbed his elbow joint, yanking him off-balance and pulling him back to face her. Probably out of surprise, he didn't stop her. "Stop it! Just shut up and think! Look at what you're doing! Listen to yourself!" A sob hitched in her vocalizer. "It's that stupid Primus-slagged synthetic energon. It's changing you! Screwing with your processor, not just your frame. You can't even…please, Dad! Just come back to base…"

"Nonsense!" Ratchet snapped, jerking his arm out of her grip. "I've had about enough of this. From all of you!"

"That is enough, Ratchet," Optimus said firmly. "It's clear that Echo is right. The synthetic energon has impaired your judgment." His optics narrowed slightly. "I'm confining you to base until further notice. Bumblebee, bridge us back."

The bridge opened immediately, a few yards away. Ratchet looked from Optimus, to the teary-opticed Echo, over at Bulkhead and Arcee, who were both glaring at him. After a tense moment that stretched out far longer than it should have, the medic growled, "Fine. If that's how you want to be." Turning on his heel, he stalked toward the groundbridge, completely ignoring the other four Autobots.

Echo's shoulders slumped in relief as Ratchet vanished into the bridge. A heavy servo touched her arm, and she jumped and looked up at Optimus. "I-I'm sorry about…" Her voice trailed off helplessly. "I didn't mean to start yelling. I just…"

"You're worried for him," Optimus finished calmly. "As, I fear, you should be. How serious are the effects of the synthetic energon?"

Echo shook her head and bit her lower lip plate. "I don't know yet. We'll have to run some tests, get it out of his system…" The groundbridge crackled, and Echo frowned and took a few steps toward it. "Bee, is there a problem?"

Before she got a response, Ratchet bolted out of the groundbridge at top speed, slamming into Bulkhead and throwing him backward into Optimus. The two 'bots crashed to the ground, almost taking Arcee down with them. Without a word, Ratchet transformed and shot off in the opposite direction from the bridge.

Echo didn't even think before transforming and hitting the accelerator. Over the comlink, she pleaded, ::Dad! Wait! Where are you going?::

No response. She pushed herself to go faster. I have to catch him. I have to.

Optimus's voice crackled with static over the comlink. ::Echo! *khhhht* We'll find Ratchet's signal and *khhhht*:::

::Optimus, say again, you cut out,:: Echo responded nervously. There must be some kind of major mineral deposit. The comms are half down. Oh, Primus, that synth-en increased speed too…what if I can't catch him? What if…

::Return to *khhht*. Echo, do you *khhht*:: The comm cut out completely. Echo winced and tried not to panic. Okay. Think. I don't know where he's going. His signal's gone – it must be scrambled by the new energon. But I've got the synth-en signal on radar. I can follow that. I have to catch him. He has to listen. He just has to. Her spark pulsed in worry and fear. What's the point of being a medic if I can't save my own father?

The terrain got rougher the further she drove. It was hard to keep her wheels steady, and several times she almost skidded over small cliffs when she didn't see a turn in time. The only bright spot she could find was that the rough ground would slow Ratchet down, too. She wasn't sure how far they'd driven. Dad, what are you doing? What's happening?

Then several other signals popped up on her heads-up display, and Echo braked abruptly and nearly crashed into a rock. ::Hello? Echo to base! Code red, repeat, I have multiple 'Con signals in the area. Hello?::

If the others could hear her, they weren't able to respond. Echo cycled her vents and edged forward until one more signal appeared – an energon deposit. A massive one. What is... She scanned the area until she spotted the source: a bot-sized tunnel, partly disguised by a hologram emitter. It had probably been a lot more effective before someone smashed it.

Dad. Echo looked around cautiously before transforming and silently ducking through the entrance. She didn't need to duck – it was probably made for a miner – but it felt stealthier somehow. I'm not built for this. Something crunched under one pede, and she flinched. Not because of the noise, but because of the thought of what it might be. With the way Dad's acting…and there's 'Cons in this tunnel…

Her scan picked up the synth-en not too far away, and she tiptoed in that direction as quickly as she could while still being quiet. Please don't be in a fight, please don't be in a fight…

Then she heard the crash. Seconds later, Ratchet's normal signal appeared in her display, and her optics widened. That could only happen if the synth-en had been removed…and the only way it could be removed so rapidly…

No! Echo forgot all about stealth, and ran for her father's fading signal.

She skidded around a corner just in time to hear KnockOut's familiar smug tone. "…your contribution to the Decepticon cause is very much appreciated…"

Horror slammed through her spark, and she froze, just out of sight in the tunnel entrance. Ratchet was sprawled on the ground, a massive wound visible on the left side of his torso. Echo realized dimly that her coding had kicked in, because she was analyzing the injury without even thinking. Crushing and lacerations. Internal and external bleeding. Severe energon loss. Green synth-en had pooled around her father's frame. She wanted to run to him, try to fix it somehow, but her limbs just weren't responding.

KnockOut was still talking. "I'll be sure to boast of your accomplishment when you're gone."

No. No! Echo managed a step forward. Then another. Neither mech had seen her yet. KnockOut lowered a spinning saw toward Ratchet's head.

"Which will happen in three…two…"

Between "two" and "one", Echo's frame started working again, and suddenly she was across the small cave, slamming fist-first into KnockOut's chest. "NO! Leave him alone!" He had a size advantage, the rational part of her processor noted as the Decepticon stumbled backward, but that didn't do much good when he was off-balance. Echo landed on both pedes and one servo and immediately pushed herself upright, standing between KnockOut and Ratchet with her blades drawn.

KnockOut stared at her in disbelief for a moment before laughing. "Well, look who it is! Couldn't just watch Daddy bleed out, hmm?" He smirked and stalked back toward her, saw humming ominously. "Tell you what. You get out of my way and let me do my job, and I'll let you live."

Echo shook her head, a single word rasping its way out of her vocalizer. "No."

"No?" KnockOut chuckled. "Come on, you know you can't beat me. How painful do you want this to be?" He pulled his arm back, and Echo lifted one blade to block, already knowing it wouldn't work.

As the saw came down, a servo that wasn't Echo's intercepted it, and a second later Ratchet's fist slammed into KnockOut's face and launched him several yards back. Echo gasped as her father stepped between her and the Decepticon, pushing her back gently. "…Dad?"

"Echo, go!" Ratchet grunted in pain and blocked KnockOut's next swing, struggling to shove him back. "Go! I'm fine!"

"I'm not leaving!" Panic welled in Echo's vocalizer, and she swung one of her blades at KnockOut's arm. He deflected it and kicked her away, sending her stumbling to the floor, but the moment's distraction allowed Ratchet to throw KnockOut off of him and dodge the 'Con's next attack. The spinning saw embedded in the wall, trapping KnockOut for the moment.

Barely looking at him, Ratchet staggered over to a container on the floor. Echo realized, with terror, that it contained most of the remaining synth-en. "Dad, no…"

KnockOut, still struggling with the saw, grinned. "What are you going to do, drink it?"

Ratchet ignored the Decepticon and turned to look at Echo. His optics had returned to their normal blue, and he smiled very slightly at her. "No. I'm going to destroy it." And with that, he hurled the container into the nearest rock wall, sending synth-en splattering over the ground uselessly.

"You idiot!" KnockOut wrenched the saw from the wall and turned on the duo. "Megatron will have my head for that!"

Before Echo could do more than pick herself up, ready to fight but not sure it would help, laser fire echoed from the tunnel. KnockOut glanced up, snapped, "Scrap," and bolted, but Echo hardly even noticed his departure. Ratchet's optics had been gradually dimming throughout the fight, and as KnockOut vanished, the Autobot medic collapsed onto the ground.

"Dad? Dad!" Echo ran to his side, dropping to her knees next to him. No, no, no, no… "Dad, look at me. Dad? You're going to be fine." Automatically, she reached across his chest, trying to find a way to patch the bleeding wound. "It's okay. Scans say the synth-en is out of your system. You're going to be okay."

"…Echo…" Ratchet reached up to brush her cheek, and she realized she was crying. "Echo…I'm sorry…"

"I know. I know. Don't talk, okay?" Echo blinked, vision blurring, and started prying at one of her own spare panels. "The others are here. We're going home. Just hold on…." As Optimus reached the two medics, Ratchet's optics faded completely to black and closed. Echo nearly choked on tears. "No. No…"

Hours later, at the Autobot base, Ratchet's optics finally flickered back online. Echo, who had been half-dozing off, bolted upright. "Dad? Oh, thank Primus!" She pressed her servo against his shoulder, holding him down. "Don't. You…you lost so much energon. I thought…" She swallowed back a sob. "You're going to be fine."

"Echo. Oh, Echo. I'm so sorry." Ratchet's servo wrapped around hers, solid and reassuring. "I'm so sorry. I never meant to hurt anyone. I only wanted – "

"To help. We know." Echo blinked rapidly and leaned down to rest her forehead against her father's shoulder. "I know. It's okay."

"It is not okay." Ratchet shook his head and winced. "No. I hurt you. I let you down. And not just you – the whole team. It was unacceptable." His servo tightened around hers. "I promise you, it will never happen again. Never."

Echo closed her optics, tension that she hadn't know was there easing. "I'll hold you to that."

"I'd be disappointed if you didn't." Ratchet's thumb stroked the back of her servo lightly. "What happened to the rest of the synth-en?"

She shrugged as best she could with her head on his shoulder. "I got rid of everything that was left here. I don't know if KnockOut managed to get any, but…"

"Don't worry about him." Ratchet stared up at the ceiling with a small sigh. "It obviously needs further testing before it's safe for anything. Even he's not stupid enough to use it after seeing that."