Heather and Sierra

The Heather-Sierra Conflict is about the conflict between Heather and Sierra.

Overview
With two new potential targets for alliances with the start of Total Drama World Tour, Heather decides to go after Sierra from the start, seeing that her other new potential target, Alejandro, was so phony and fake that he obviously had another motive, making Sierra the safer potential ally. However, having seen the first two seasons multiple times and knowing of Heather's infamy on the show, Sierra knows of what Heather can pull and decides to manipulate Heather's manipulations to her own advantage. Ultimately together on Team Amazon, both go through periods of liking and hating one another with one trying to manipulate the other for their own motives, going from complete friendship to utter disrespect for one another. Heather admires Sierra's knowledge for the show but sees her as utterly insane, while Sierra sees Heather as a fellow female friend but knows of her evil and manipulative manner. Ultimately by the end of the season, Heather and Sierra do gain respect for one another, particularly after Sierra becomes eliminated and loses her hair in the process and Sierra supporting Heather after her beloved Cody becomes eliminated.

Celebrity Manhunt's Total Drama Action Reunion Special
When Sierra says she knows everyone's dental records, Heather calls her a stalker.

Walk Like An Egyptian - Part 1
Heather tries to form an alliance with Sierra, to counter Alejandro's possible alliance with Lindsay. Heather pretends to like Sierra, but is actually very annoyed by her. In the confessional Heather says "I do NOT heart the new girl". At one point, Sierra sets off a trap that sends a row of arrows toward Heather's head, Heather is visibly angry, but she is able to control herself and pretends to forgive Sierra. Heather joins Sierra in a group hug with Cody, although she seemed reluctant to do it. Sierra seems to be unaware that Heather dislikes her, which appears to be quite odd, since Sierra supposedly knows everything about the contestants and should know of Heather's manipulative nature.

Walk Like An Egyptian - Part 2
Heather quickly agrees to switch Izzy for Sierra, possibly to further the alliance Heather wants with Sierra. She started to regret this when they didn't manage to put the camel inside their canoe. But in the end, with the help of Alejandro and Izzy the camel finally got inside of it and Team Amazon won the challenge.

Broadway, Baby!
Sierra states that she knows that Heather is playing her so she's playing Heather back by pretending to be played. And when Team Amazon is receiving their rewards Heather tells Sierra to not talk to Chris so that he'll forget how creepy she is, however Heather quickly corrects herself by calling her "special" instead.

Slap Slap Revolution
Heather was seen sitting together with Sierra in the winner's cabin. Sierra was telling Heather how she has become the president of her fifteenth total drama fanclub. Heather wasn't very interested in this, but changed subjects asking if Sierra has any idea of who will be the next eliminated. Sierra confirms and states that Team Chris Is Really Really Really Really Hot is the next to lose due to overconfidence. Right after this, Sierra appears in the confessional and tells that every time Heather thinks she is using her, she makes a little notch on her belt. She took it off from her pants, showing her underwear and seven notches in her belt. This may have confirmed that in previous episodes, Sierra was truely aware of Heather's tactics, but didn't show it.

The Am-AH-Zon Race
When Heather found out that the Zing-Zings were just teenage Peruvian actors, Sierra comments that Heather isn't the goddess she thinks she is. Sierra decides to join Gwen and Courtney to vote Heather out, and was shocked when she discovered it was a fake elimination ceremony.

Jamaica Me Sweat
Heather calls her "fanzilla" when Sierra ends up splashing all the members of Team Amazon after her dive.

Sweden Sour
While trying to get Alejandro's attention away from Courtney, Heather claimed that she got some gum on the back of her butt. However, Sierra ruins it as she points to Heather that she doesn't have any gum on her. Due to Heather's dislike of Cody, when Heather was trying to hit Cody with a piece of wood, Sierra was then chasing her with a piece of wood.

Rapa Phooey!
Sierra was making fun of Heather and Alejandro and how they are obsessed with each other. Sierra knows not to make a permanent alliance with Heather. And when they were singing Condor, Cody Jr. went to Heather and Sierra said "Cody Jr! No not auntie Heather!" much to Sierra's displeasure of Cody Jr.'s attraction to Heather.

Awwwwww, Drumheller
Sierra was angry at Heather when she thought Heather slept next to Cody in commercial cabin. During the design-o-saur vote, Heather voted for Sierra due to her secret love of glitter glue and Sierra voted for Heather because the Chris dinosaur reminds her of her mom. Then later, Sierra squirts pink paste in Heather's face out of her fury, to which Heather responds to "Real mature.". After finding out about the truth between Cody and Heather, Sierra agreed with Cody to vote out Alejandro and not Heather. When Heather was in the confessional, Sierra popped in and Heather begged her not to murder her.

Planes, Trains, and Hot Air Mobiles
Sierra states that she can't let Heather win while at the firework stand.

Hawaiian Punch
Sierra cheers for Cody to win in the beginning of the episode, instead of Heather or Alejandro.

Walk Like An Egyptian - Part 1
Heather is seen running with Sierra and Cody from the "mummy" that is chasing them, then later in the episode Sierra hugs Cody and Heather reluctantly agrees to hugs her and Cody to keep the alliance going on.

Super Happy Crazy Fun Time Japan
Heather stood up for Sierra, saying that the team should consider Sierra's opinion when Courtney was saying she should be team leader.

Slap Slap Revolution
Sierra and Heather were seen sitting beside each other in first class, with Sierra telling Heather about how she became the president of her blog.

Sweden Sour
When Heather was singing at the beginning of Gwen's Face, she seemed to be cautious that she was singing to Sierra.

Niagara Brawls
When Sierra was stuck with Alejandro as her husband, Heather stepped in and said she'll take Alejandro from Sierra. Sierra replied, "That's fine with me".

Rapa Phooey!
Sierra was seen complaining to Heather about Cody and Alejandro. Heather said she didn't know anything about being a psychiotrist. Heather and Sierra teamed up and Sierra even made Heather a pouch to keep her eggs in. They were actually nice to each other for the first time. They were seen running from a boulder together and got along fine. They both said that they disliked Alejandro and wanted him gone.

Awwwwww, Drumheller
Heather voted for Sierra's dinosaur and admitted that she has a collection of glitter glue. Sierra also voted for Heather's dinosaur because she loved the idea that it was a Chris dinosaur and said she'll have to remember that idea. Also when Sierra accidentally blows up the plane, Heather appears to be concerned.

Planes, Trains, and Hot Air Mobiles
When Cody dug up Sierra from the rubble, Heather went and got her a wheelchair and a green feathered hat from Rapa Phooey!. In the confessional, Heather says no girl should be bald on television and states she knows the feeling of being bald.

Hawaiian Punch
Sierra was seen cheering when Heather kicked Alejandro in the groin. She also looked concerned when Heather and Ezekiel fought over the million dollars.

Trivia

 * Both were members of Team Amazon, although Sierra was originally a member of Team Chris Is Really Really Really Really Hot.
 * Both made it to the final four in Total Drama World Tour.
 * Heather did so twice, her first time being in Total Drama Island.
 * Both were the final 2 females left competing in Total Drama World Tour.
 * Both dislike Gwen, Alejandro, Blaineley, Chris and Courtney.
 * They both had fake eliminations in Total Drama World Tour.
 * Both have been bald near the end of their debut season.
 * Heather at the end of Total Drama Island and most of Total Drama Action.
 * Sierra in Awwwwww, Drumheller and the end of Total Drama World Tour.