Thresh, the District 11 boy tribute. He saves Katniss because Katniss was helping Rue (his district partner who had died by then via Marvel from District 1), however, Thresh mistakenly thought it was Clove who killed Rue.
He, like Katniss did not like to owe someone anything, and liked to clear any debts away as soon as he could.
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Peeta
Well it's a match to the death so you would try not like any one. Because you would have to kill them. And Clove had a good chance of winning so wen she sall that Katniss was good she did not like her. Also Clove is just a bitter person. That the only things I can think of.
At the Feast Clove attacks Katniss, but before killing her she makes a foment about Rue. Thresh hears her and grabs Clove. Enraged he hits her with a rock and she slowly dies. He doesn't kill Katniss though because she was Rue's ally and feels that he owes her. Being from the Seam Katniss understands perfectly. She feels the same debt to Peeta since he gave her the bread when they were little.
Katniss : Peeta and Gale :: Cato : Glimmer and Clove District 12 : Coal :: District 7 : Lumber Katniss : Peeta :: Cato : Clove
Clove says "Where's your boyfriend, Lover Boy, District 12? Still hanging on? We'll just let nature take care of him." Then as Clove is about to kill Katniss, Thresh comes up and kills Clove with a rock.