Mags is clearly aware of the plan, as Finnick has included her in their alliance. He watches after her and brings her water from the tree when she is dehydrated and exhausted. However, in order to protect Katniss, Mags sacrifices herself to the poisonous fog so that it wouldn't kill Katniss and Peeta.
Finnick couldn't carry both Peeta and Mags, so Mags heroically sacrificed herself by walking into the poisonous fog to allow the group to move at a faster pace. It was later revealed Mags was part of a bigger alliance to ensure Katniss and Peeta's survival.
Given that she is willing to make the ultimate sacrifice to protect Peeta, it's safe to assume that the Morphling was committed to the rebel cause. Like the other victors, she knows the power that Katniss has as a lightning rod for the rebellion, and she knows that Katniss will not help without Peeta.
Early on in Catching Fire, it was made clear that Mags didn't talk, and instead, she used hand gestures to communicate. Interestingly enough, her inability to speak was never directly explained in the movies. The book, on the other hand, insinuated that it was due to a medical condition.
Chia Mags kisses Finnick on the mouth to briefly let him know that this is the last time she will see him. It's her way of saying "Goodbye" but in a more affectionate way.
Poisonous Fog Descends | The Hunger Games: Catching Fire
Why were Finnick and Mags so close?
Also, Mags was Finnick's mentor, and most likely helped mentor Annie. They would have all lived together in the District 4 Victors' Village. Much like how Katniss, Peeta, and Haymitch became family, it is probable Mags, Annie, and Finnick did as well, so Mags may have felt a maternal kinship towards the younger two.
While in training for the third Quarter Quell, Katniss watched as Mags displayed her skill of being able to make fishhooks out of nearly anything. This skill, plus the fact that she volunteered to take Annie Cresta's place, made Katniss want Mags to be one of her allies in the arena.
Catching Fire's Mags Flanagan was District 4's female tribute in the 75th Quarter Quell, along with male tribute, Finnick Odair. At 80-years-old, she was the oldest tribute.
The following year after Lucy Gray Baird's victory, another female tribute emerged as the Hunger Games winner. Mags Flanagan became the first victor from District 4, living off of nuts and her survival skills by creating fishhooks.
District 12 has the most Hunger Games victors, with five winners, including Katniss, Peeta, Haymitch, and Lucy Gray. Finnick Odair is the youngest winner in history, winning at just 14 years old.
Johanna won the 71st Hunger Games by pretending to be weak and that made all the other tributes leave her for last. Then she unleashed her full potential and violently killed all the remaining tributes. Johanna, being the only remaining District 7 female victor, was Reaped for the 75th Hunger Games.
Annie Cresta is one of the victors of District 4. She won The 70th Hunger Games at age 18. She also got married by her mentor, Finnick Odair. She suffered from PTSD after her Games, after seeing her district partner being beheaded by a Career during the Games she was in.
Mags is clearly aware of the plan, as Finnick has included her in their alliance. He watches after her and brings her water from the tree when she is dehydrated and exhausted. However, in order to protect Katniss, Mags sacrifices herself to the poisonous fog so that it wouldn't kill Katniss and Peeta.
The rules for the second Quarter Quell stipulated that double the number of tributes were to be reaped from the districts for the Games. At the age of 16, Haymitch was reaped as one of District 12's two male tributes for the 50th Hunger Games alongside Maysilee Donner and another female tribute.
The films, trying to be as faithful to the source material as possible, naturally had to include Finnick's death as well. In this sense, Finnick is the perfect candidate for upping the stakes of the plot via his death, as his hope for a future with his partner Annie made his demise seem even more untimely.
She's half-family, i.e., sorta or partially family, because there's affection but not blood relation. There are literally only 2 people in Finnick's family (Mags and Annie), and Mags is 1 of them.
Finnick also cared a lot for his mentor, Mags, who had volunteered to participate in the Games, instead of Annie. Finnick was close friends with Johanna Mason and fairly good allies with Katniss, Peeta, Wiress, and Beetee.
As Katniss gets to know Finnick during the Quarter Quell, she sees he is in fact loyal, dutiful, and caring. For example, despite Mags being a burden on his chances of survival, Finnick does everything he can to keep the eighty-year-old alive because, as we learn, she was his mentor and he genuinely cares about her.
She clearly loved Finnick and Annie, as it was noted she basically raised Finnick, having mentored him and likely Annie as well. She made easy friends with Katniss, who admired the old woman for her bravery and selflessness.
Prim (Willow Shields) was an important character, as Katniss only volunteered in the games to protect her. Arguably, many viewers find that the fixation on Prim's death took away the due respect that other characters deserve. But as the films follow Katniss, Prim's absence affects her most profoundly.
Both Morphlings die during the Hunger Games in Catching Fire, after the female tribute from District 6 protects Peeta from the monkey mutations that attack the tribute. She dies in Peeta's arms while looking at the sunset.
With the last killing occuring before an hour had even passed, these games shocked the Capitol audience and are the quickest in the history of the games.
In the 75th Hunger Games, Finnick Odair from District 4 had a token that was a gold bangle with a flame pattern. This token was first given to Haymitch Abernathy from Effie Trinket as a sign of them being a team. Haymitch gave it to Finnick to tell Katniss to make him an ally, as he could later help her in the games.
He only uses Katniss because the Capitol is brutally oppressive and he realizes that, with Katniss's help, the rebels have a real chance of bringing it down. This sort of cynical pragmatism largely defines Haymitch, and it stems from a combination of realism and a rebellious spirit.
Peeta used the dyes to paint a picture of Rue after Katniss covered her with flowers when she died. He says he wants to hold them accountable for killing Rue, and Effie tells him that that kind of thinking is forbidden. Katniss then tells the team she hung a dummy of Seneca Crane.
