Sage mentions that the Red Sentients were the ones who started and progressed the war Though by the Season 2 finale, they are tired of the conflict and make peace. In the third season Korosivash and Karmakaris prove that they're not evil, and the Red Sentient 5 seem to be the exception.
Butt Monkey: Stanford on more than one occasion, though he has a tendency to be somewhat of a Jerk Ass, so it's sometimes deserved. Then again, he has got better as the series has moved on, so it has become less frequent.
This is Grimian's fate as well. Kalus beats him, destroys his ride, and banishes him, but spares his life so he can live in shame. However, Kalus doesn't give him a thirdCruel Mercy after that and is heavily implied to have killed him.
While Zemerik didn't mean for it to be, Krytus defiantly sees Zemerik forgiving him as this, as it robbed him of his eons old revenge.
Cult: The Alpha Code, a third Sark faction that are green in color. They dwell in a temple within the Torborian Badlands and worship a strange entity dwelling at the bottom of a deep pit. They sacrifice Zemerik and Zug to it.
The End... Or Is It?: After the Karmordians have been finally defeated in Full Revolution, the final scene is a partly recovered Zemerik reactivating Zug and telling him they have a lot to do.
Enemy Mine: Between the Battle Force 5 and the Sark at the end of Season One. Lampshaded by Stanford:
Stanford: Talk about nerve! Zemerik's Axis of Evil went all pear-shaped, so now he's suggesting an Axis of Good?
It appears that this alliance is still in effect as of Season Two:
Agura: We've really gotta tweak our spam filter.
Vert: Hold on, Zemerik's on our side. Sorta.
As of Blue Tide, this alliance is definitely over.
Happens in Shadow Runners when Krytus and Vert end up stuck in the Shadow Zone. Though in this case its mainly because if Krytus' shell gets destroyed, his energy form would react with the Shadow Zone and cause a supernova-like explosion that would destroy the multiverse.
In Grimian's Secret, the team has to team up with the Vandals to stop Krytus and the Red Sentients from conquering Planet Vandal.
Energy Absorption: Both Kyburi and her vehicle are able to do this to machines such as Sark and the BF 5's vehicles.
Apparently, she can also do this to organic beings.
Engineered Public Confession: When the team is hurled into the past, they end up having to use one to expose Krytus for what he really is to not only his sister, but the entire Blue Sentient race in the form of a fiery Villainous Breakdown in the middle of an important event. Originally he did this himself, but due to accidentally altering history, they had to do it in order to Set Right What Once Went Wrong.
Fake Defector: In Better Off Red, Vert pulls this on Krytus, pretending to switch sides and agree with Krytus' argument that Sage must be stopped in order to save the multiverse. Turns out he was really finding out the location of a series of Red Sentient devices that transported them to their Respawn Chambers so they could destroy them. He also swiped the last remaining Blue Sentient one from Krytus in the process.
Fantastic Racism: Both the Sark and Vandals refer to humans as "organics" and "sub-species" in extremely derogatory manners.
However, the term "organic" probably refers to all organics in general, including Vandals.
Fastball Special: Sherman throws Spinner during their first fight, before they even get their vehicles.
Five-Man Band: Despite the name, there's actually eight members; although, only five vehicles are allowed through portal at once, and two of them share a single vehicle.
Five-Token Band: With the exception of Vert, all the team members are some sort of minority. Agura is black, Zoom is Japanese-American, the Cortez bros. are Hispanic, and Stanford is British. And royalty.
New member Tezz Volitov is Eastern European, possibly Serbian. This series likes this trope.
But wait, there's more! The latest addition to the team, AJ Dalton, is Canadian, eh?
Heroic Sacrifice: Occurs in "Rumble in The Jungle" when Tromp activates the bomb to destroy the Vandals' Sentient-based technology, stranding himself on Planet Vandal, but Tezz swears to come back for him. Unite And Strike confirms this, as he's seen next to Tezz at the end.
Hulk Speak: Kytren has a tendency to speak in sentence fragments:
"Detect enemy. Destroy enemy."
"Kytren fight two fools. Come. Test."
"Human warn others."
I Call It Vera: Zeke calls his rusty old pickup truck, er, "Trucketta".
Mind Hive: The stored minds of the entire Blue Sentient civilization were hidden in Sage's subconscious! If she learns this, however, it will trigger their release. They're finally released to their bodies at the season 2 finale.
Krytus does this to Zemerik at the beginning of Season Two.
Oh Crap: Krytus gets a double dose of this in Unite And Strike when Sage and the rest of the Blue Sentients are restored and blast him. When he gets out of his Respawn Chamber to take over the newly revived Red Sentients, he gets this again when he discovers the Blue Sentients had gotten there first and that the entire Sentient civilization is sick and tired of the war he started.
Old Master: Master Takeyasu. He was able to destroy the Venikus in one blow, held his own against Kyburi in hand-to-hand combat for a while, somehow knows Krytus, and he's respected by Rawkus, which is no easy feat!
Once per Episode: Along with being a Fusion Dance, the Fuser technology. Justified in that it was the result of an unstable compound being loaded into an untested, experimental prototype, and also in that it only has one charge per mission.
One-Man Army: When the Battle Force 5 went to investigate news of La Résistance on one of the Red Sentient Moons, they discovered that Tezz Volitov WAS the rebel army. For perspective, this guy single-handedly destroyed hundreds, if not THOUSANDS of Red Zurk using his expertise in electromagnetism.
The Psycho Rangers: Battle Force -5. Dark versions of the heroes' outfits? Check. Always bickering? Check. Evil Sherman even has a Perma StubbleBeard of Evil. One trope is played with; it's easy for Evil Vert to simply wipe off what appeared to be a tattoo, the only thing physically identifying him as not-Vert.
Public Execution: Grimian is last seen being held at spear point before the entire Vandal horde, Kalus approaching him with a spear and a Slasher Smile on his face, strongly implying that he's about to be executed before the entire planet for treason.
Recruit Teenagers with Attitude: Played straight. When one of the six youth rather sensibly asks their holographic Obi Wan why they alone were chosen to save the world, she replies that each one brings "something different" to the team. Which one brings driving experience to a battle for the fate of the world that involves high-speed racing is never said. Whether this is Lampshade Hanging or Better than a Bare Bulb is entirely in the eye of the viewer.
Not to mention that each member was recruited because they were "the best of the best". They already know how to drive, but they each contributed a specialized role to the team. In fact, it was summarized pretty well when Vert reconsidered the need for a team in the first episode:
Vert: A team's starting to look good right about now.
(looking at a large group of Zurk) Someone to do some scouting, someone with ranged attacks,
(notices Zug) some heavy muscle... Yeah, that would definitely be nice.
Continued with the two new members as well: Tezz, while overconfident, brings a great deal of scientific knowledge to the team and is a technical genius. AJ is accustomed to winter conditions, and his Gear Slammer gives them more options for their muscle.
Running Gag: Stanford is really not fond of Planet Vandal. "I HATE THIS PLANET!"
Russian Guy Suffers Most: According to the webisode "Lost Charge" poor Tezz was stuck on that Red Sentient moon for 3,286 days before the Battle Force 5 showed up. He was NINE YEARS OLD when he was stranded, and spent the NEXT nine years barely scraping by (iff his emaciated figure is anything to go by) and fighting Red Sark, as presumably the only humanoid or even living creature on that moon. And you never hear him complain about it.
Sealed Evil in a Can: The five Red Sentients were imprisoned by Zemerik. Krytus was freed by Praxion and then proceeded to free the other four himself.
At the end of season 2, the rest of Red Sentients turned out to be a subversion, as they were just as sick of the war as their blue counterparts. Instead of joining Krytus against them, they make peace and Krytus is imprisoned once again, this time in a block of ice in a frozen zone.
Twofer Token Minority: Agura. Black and the only girl on the team. Of course, the team is 5/6 token anyway.
Vague Age: While some fans believe that BF 5 could be in their early 20s, the official Battle Force 5 website describes our heroes as a "team of teen drivers."
Vagueness Is Coming: In Better Off Red, Sage states that a new enemy is on it's way and she's building a weapon to fight it. According to her, this new threat is even worse than the Red Sentients and was something she hoped they'd never have to face.
See also Foreshadowing above.
At the season two finale, Rawkus states a new enemy (likely the same one Sage was worried about) called the Ancient Ones has awakened and their evil is so great, even he is fully behind the Battle Force 5 to face them.
Was It Really Worth It?: Krytus poses this question to Sage about her freezing of the Red Sentients to stop him. It's subverted as, while she didn't want to do it, she states that yes, it was worth it because Krytus was a threat to the Blue Sentients and the entire universe. Krytus actually agrees with her, but really could care less.
Your Costume Needs Work: When the Vandals and Sark finally reach Earth in "Axis of Evil", they are mistaken by the locals for movie actors, with their 'costumes' being described as "faker than a three-dollar bill."
Your Princess Is in Another Castle: At the finale of season 2, the Red Sentient 5, Vandals, and Zemerik have all been defeated, peace reigns...then Rawkus reveals a new evil called the Ancient Ones has been unleashed.