Another ultimate weapon located within “Final Fantasy VII” is Tifa's Premium Heart, which packs quite the punch. After events at Mideel and Cloud has returned to the party, players can go digging at Bone Village, for a chance to obtain a special key, the Key to Sector 5, which will allow the player back into Midgar.
Once in Midgar, the party must head over to Wall Market, and inspect the broken or 'fake' item shop, and Tifa's ultimate weapon, Premium Heart, will pop out. It is also good to note that this can be done before Cloud is returned to the party, if the player travels to the shop with both Cid and Tifa in the active party. This will prompt a scene in which Cid fixes the broken machine within the automated item shop, and out falls Tifa's Premium Heart.
Much like Barret's ultimate weapon, Tifa's does not provide any stat boosts, yet unlike Barret's ultimate weapon, Tifa's does not give her long range status either. Fortunately, the special effect of this powerful weapon makes up for such shortcomings. The damage of Premium Heart is calculated by how close to full Tifa's Limit Bar is, multiplied by her Limit level.
Basically, if Tifa had all four Limit levels, and her Limit Bar were full, then it would be a full Limit Bar * 4, however the Limit Bar is calculated in numbers. So as the battle progresses and Tifa takes more blows, she becomes stronger and stronger, and once her bar is full, she is able to unleash a potential 7-hit combo on an enemy or enemies, which will most likely do maximum 9,999 damage per hit.