My power rankings on the og
Cleo: Cleo is the Most Powerful (Peak Potential) if Cleo taps into bloodbending, she wins any fight. It does not matter how much fire or lightning Rikki can generate if Cleo can freeze the blood in Rikki's veins, stop her heart, or physically force her arms down to prevent her from using her hands.
Rikki: Rikki’s powers are more destructive and dangerous Her ability to trigger electrolysis, melt metal, or throw lightning makes her a living weapon. Due to her high energy, explosive power.
Emma: I mean there’s no explanation as to why she’s last but here’s why: Emma deals with solid mass. In a fight, Rikki can instantly melt anything Emma creates, turning Emma’s ice walls into water for Cleo to use. If Cleo is bloodbending it prevents her from being able to use her hands. Emma’s peak potential is essentially controlling the weather (blizzards and storms). While dangerous, it does doesn’t compare to Rikki’s and Cleo.
Btw all these are if they all fully tapped into their elements.