Believe it or not, Tifa is another one of your stronger party members. She uses her fists with the utmost lethality, and can rival Barret or Cloud at high enough levels. Her limit break is unique, in that instead of you picking what limit break she uses, she uses all of them. This makes her perform a deadly combo of seven hits, obliterating anything unfortunate enough to be in it's way.
Tifa was born in the same town as Cloud, Nibelheim. She had some distress at Cloud's leaving to be in SOLDIER, but figured it would be for the best. She made him promise that when she needed help, he would come to rescue her like her own knight in shining armor. He promised, and left. She was injured gravely when Sephiroth was driven insane on his mission to Nibelheim, and would have been killed if not for Clouds heroics. Had she known it was Cloud who had saved her, she might never have pulled him into joining AVALANCHE.
Cloud is reunited with Tifa after the successful bombing mission in Midgar. Cloud claims that once he is paid he will split, but Tifa convinces him to stay. She reminds him of his last night in Nibelheim, where he promised to protect her and come to her rescue. He gives in, and proceeds for another bombing mission... for double what Barrett was originally going to pay him! One his way back however, he is seperated from the gang. He meets up with Aeris, and when they had almost returned to Tifa's house, they see her being kidnapped by a twisted rich-man. Cloud and Aeris rush to save her, and fall head-first into a struggle much larger than Tifa could have ever dreamed.