Chapter 11 is rather similar to Chapter 10, in many ways... excluding the boss fights. A fairly linear dungeon full of trash mobs, First Strike Materia will help Cloud use "Triple Slash" at the outset of each battle, and will help Aerith use Fire + Magnify. Both serve the same end - to finish fights quickly and with as little fuss as possible.
|Useful Materia:||Fire + Elemental (weapon), Healing, Revive, First Strike, Steadfast Block, ATB Stagger, HP Up|
|Useful Materia:||Fire + Magnify, Healing, Revive, First Strike, ATB Stagger, Magic Up, HP Up|
|Useful Materia:||Fire + Elemental (weapon), Healing, Revive, Steadfast Block, ATB Stagger, HP Up|
Your first fight will be against some Wererats. "Triple Slash" should take care of things as quickly as it ever did.
The second battle, against a trio of Cripshays, shouldn't break the paradigm, either. A combination of "Triple Slash" and Fire + Magnify will get you through this - and follow-up encounters - quickly and simply.
Fight your way to the Maintenance Facility, stopping to grab another orb of HP Up Materia, should you still need/desire another piece.
Ghosts will prove to be a minor nuisance, demanding a slight alteration to the formula that has served you well so far. Start out the fight with Fire + Magnify and when it nullifies magic damage, switch to Cloud/Tifa and finish your foe off with "Triple Slash" or ki abilities.
Use the above tactics against the foes you come across in the Maintenance Facility and you should get through without much trouble. Don't engage in unnecessary fights and you may even make it through to the northeastern corner without needing to heal. Here a rest bench awaits, beyond which is the fight with the Ghoul. As with most hard mode bosses, the Hard difficulty encounter with Ghoul will be covered on its own page. You'll obtain the Telluric Scriptures Vol. X Manuscript for defeating the Ghoul.
After defeating the Ghoul, you'll have to fight a pair of Lesser Drakes as you go to leave the Maintenance Facility. They're nuisance foes, since their ability to fly makes it difficult to hit them with any powerful attacks, and Aero is unreliable. No finesse here, just cut them down and block their "Tornado" attack, all the while wishing you had Barret around.
At the northern end of the Maintenance Facility you'll find another rest bench, which is nice, as a lengthy encounter awaits just outside. Activate the switch, the fend off several Wererats, two Ghosts and finally four Cripshays. Once done, use the previous rest bench, then continue on.
The only other battle left in this chapter - save for the second boss fight - is an encounter with another Lesser Drake and a Cerulean Drake. For this battle we equip Ice + Elemental on Cloud and Tifa's armor and focus on just pummeling the winged reptiles to death - the Cerulean Drake will keep us healed and we won't need to worry too much about being competent.
Next you'll face off against Eligor, who was a nuisance in Normal difficulty, a distinction Eligor isn't keen to relinquish in Hard difficulty. As usual, you'll find the strategy for the Hard difficulty version of Eligor on its own page. For defeating Eligor on Hard difficulty you'll obtain the Way of the Fist Vol. VIII Manuscript.