I have a theory that Rattrap is actually an Onyx Prime agent He at the same time that helping Starscream, he also saved Prowl, helped Windblade and gave the message to the Combaticons on Swindle, but if he really wanted to depose Strascream he could have helped more, as for example he saw Startscream talking that killed Metalhawk and did not tell anyone. All this because the plan of his master (Onyx) is to destabilize Cybertron, sowing discord and chaos, but still not enough to be deposed Starscream and ends up making a better ruler is elected.
I think that's pretty likely now. Though around when Sins of the Wreckers started. I thought Rattrap was part of Tarantulas's group also.
I'm still trying to figure out Rattrap, it is possible he's an agent of Onyx or just maybe doing his own game, but what makes this more frustrating for me: It's Rattrap! He's one of the good guys, and here he is being a schemer. Really heart breaking for a hardcore Beast Wars fan like me seeing him like this, gives me flashbacks too of episode 6 of Beast Machines where his loyalty was brought into question. I mean I've gotten used to it, this is a different universe after all, but it feels odd seeing him play the role of Starscream's minion when he briefly bad mouthed at the Starscream possessed Waspinator in Beast Wars. (And why was the Animated version, Rattletrap, such a untrustworthy creep too?) XD
This is kind of why I don't like them revisiting the Beast Wars characters in other continuities. I always feel like they lose some of their best character traits (Blackarachnia is another, either they try to make her too sympathetic oh woe is me or way too cruel and nasty and not a good in-between, girls just wanna have fun way), Rattrap in the show was a rude, crass jerk with a heart of gold but they remove most of his more likeable, honourable traits to just make him the token sleazebag. It's a shame since Rattrap at the end of the day, is still one of the good guys even if he doesn't act like it on the surface. I've grown to love Rattrap's character a lot since the past summer when re-watching Beast Wars.