Classified Intel is an activity in Final Fantasy VII Rebirth, and one of many types of World Intel. It allows the party to battle a powerful enemy that serves a miniboss for that region.
There is one Classified Intel per region, and it is unlocked by completing Expedition Intel in that region to discover it. Classified Intel is significantly more challenging than Fiend Intel, and completing it will unlock battles in the Chadley Combat Simulator challenges that grant 
Enemy Skill Materia abilities.
Locations[]
Grasslands[]
Quetzalcoatl is fought in "Classified Intel: Winged Lacertilian of Yore", the Classified Intel in grasslands. Quetzalcoatl is a flying boss that moves between the air and ground. It is weak to 
Ice, and can be pressured by inflicting enough ice damage to it. Quetzalcoatl's attacks comprise a mix of 
Lightning-based attacks and melee attacks wherein it charges at the party.
It is crucial to equip 
Ice Materia and/or Fire and Ice Materia on one or more party members, so as to be able to pressure it with 
Blizzard or Blizzaga. Healing Materia is important to bring along, and Prayer Materia or Chakra Materia are nice bonuses, due to the damage the enemy deals. If desired, Steal Materia can be brought to steal its talon. For this battle, alongside Cloud, bringing Tifa is an excellent choice so she can increase stagger bonus damage quickly with her Unbridled Strength attacks.
The aim should be to guard against or dodge quetzacoatl's attacks early, and cast ice spells to pressure it. From this point on it can be staggered quickly, and stagger bonus damage should be built up with Tifa to then deal as much damage as possible before it recovers. At this point, simply rinse and repeat to defeat the boss.
Junon Region[]
Mindflayer is fought in "Classified Intel: The Whisperer in the Darkness", the Classified Intel of Junon Region. Mindflayer has no elemental weakness, and deals heavy magic-based damage, and is capable of locking a party member into a hold. Its most powerful attack, Pyschotic Break (which it uses after Telekinesis), can wipe the party if not avoided, but debris appears in front of it while charging its attack to make this avoidable.
Synergy abilities are the only means of pressuring mindflayer. As such, use of Time Materia to grant 
Haste can be helpful to build up ATB gauges faster, as can passive materia such as 
ATB Assist Materia. Mindflayer resists magic damage, meaning any other materia should be for healing, or for applying negative statuses, such as through Disempowerment Materia. Red XIII can be a good party member to bring due to his physical damage, agility, and durability, while Barret also provides physical damage and durability.
Throughout the battle, simply using abilities to deal some damage, while more importantly building ATB gauges, and consuming them is best. The primary strategy will be to build toward a synergy ability to pressure it, and thereafter stagger it quickly with abilities such as Focused Thrust, Focused Shot, or Focused Strike. Any synergy ability works, as long as it attacks mindflayer.
Corel Region[]
Tonberry King is fought in "Classified Intel: Heavy Lies the Crown", the Classified Intel of the Corel Region. Tonberry King has no weaknesses, and as an extremely durable enemy whose attacks can inflict instant death, but is also very slow, and many of its attacks can be dodged with relative ease simply by evading them with well-timed dodge rolls or by keeping a good distance from it when it uses them. It will also call small tonberries for backup.
Steal materia should be brought so as to steal its Pristine Crown, which can be stolen when dropped. Equipping Revival Materia is important due to its instant death attacks, and 
Safety Bit provides a means of being invulnerable to many of these attacks. Disempowerment spells can be a good means of boosting damage against it. Yuffie is an excellent choice of party member due to her agility allowing her to dodge easily and her versatility allowing her to switch between ranged and melee attacks, while Tifa is very effective at boosting stagger bonus damage, and possesses good agility of her own.
Tonberry King is pressured by dealing damage to it as its attacks miss. This means the fight will be a battle of attrition, getting damage in between its attacks, typically in the form either of offensive spells or from strong character attacks. Because most of its attacks either inflict instant death or immobilize a party member, the focus should be less on raising HP and more on reviving any fallen party members. Any small tonberries it summons should be defeated quickly.
After pressuring Tonberry King, its crown can be stolen by using Steal (defeating it without stealing the crown will simply earn a Marred Crown). After the crown is stolen, it will remain pressured. Staggering it during pressure should provide an opportunity to deal most of the damage.
Gongaga Region[]
Great Malboro is fought in "Classified Intel: The Sultan of Stench", the Classified Intel of the Gongaga Region. Great Malboro is immune to all negative status effects, and its main attacks involve inflicting its own negative statuses, particularly 
Toad from its Bad Breath attack, and HP-draining attacks. It is however weak to the ice element.
Equipping ice materia is crucial, and pairing it with 
Elemental Materia on a party member's weapon can be extremely important for damage. Cleansing Materia is also very important for removing statuses, but equipping the White Cape accessory can block against toad from the start. Bringing mobile party members such as Tifa and Yuffie can also be particularly important to take advantage of the Great Malboro's slowness.
Great Malboro is slow in its attacks and movement, and its main damage output comes from draining HP. It can be pressured by destroying its Rank Mouth weakpoint, but simply keeping behind it and attacking it with strong ice attacks such as Blizzara or Blizzaga, and normal attacks infused by the ice elemental materia, should suffice. Make sure to constantly heal party members who are inflicted with negative statuses.
Cosmo Canyon Region[]
Jabberwock is fought in "Classified Intel: The Wyvern Awoken", the Classified Intel of the Cosmo Canyon Region. Jabberock is a large creature who can use Gorgon Shield to become immune to physical damage, but is weak to fire. It primarily deals powerful melee attacks.
Using fire materia on multiple party members is preferred, and pairing it with elemental materia on a party member's weapon is particularly helpful. Beyond this, ensuring a mix of healing spells is available will work, and any mix of party members should help.
The primary aim in the battle will be to build ATB charges and use Firaga when it uses Gorgon Shield, to instantly pressure it and remove the shield. Firaga can also provide a major source of damage after staggering it.
Nibel Region[]
King Zu is fought in "Classified Intel: Avian Tyrant", the Classified Intel of the Nibel Region. It is an immense flying enemy, which is weak to Lightning. Most of its attacks are very damaging, but its Swan Song attack in particular is devastating, and can easily wipe the party if not defended against.
It is important to bring Lightning Materia on multiple party members, one of whom can pair it with elemental materia for damage. Bringing means of healing or protecting the party is crucial, such as pairing Barrier Materia with Magnify Materia, or pairing magnify with healing materia, depending on preference. ATB-boosting materia, such as time materia or ATB Boost Materia, is important. Bringing durable party members is helpful for the battle, as is ones with strong spellcasting.
It is crucial when King Zu charges up Swan Song to immediately destroy its two wings. The quickest way to do this is to cast Thundara (or Thundaga if possible) on each attack. This will not only prevent its attack, but pressure it and leave it vulnerable. Outside this, it is important to avoid its other attacks and keep ATB charges available for when it uses Swan Song.