The Great Explosion Festival is a Trial for the Chamber of the Fallen in Final Fantasy Brave Exvius. Players face the eponymous "Bomb Family" consisting of the Mom Bomb, Dad Bomb and their children. It has a difficulty of 10★.
The trial features a multitude of Bosses, the central ones being the Mom Bomb and the Dad Bomb. They will continuously spawn their children the Bomb Juniors which act as sub-bosses.
The battle has a major gimmick in that all of the Bosses are immune to non-elemental damage of all kind (Physical, Magical, etc.) as such the player will need elemental damage to confront the Bosses. There is, however, another layer of trickery, which is that all Bosses have their respective weaknesses and resistances, being only vulnerable to their opposite element (i.e. Fire is weak to Ice, Water is weak to Lightning and vice-versa) having a major weakness to their opposite element but otherwise resisting all other elements by 300% or downright absorbing their matching element.
The Mom and Dad Bomb have each 44,444,444 HP. The Mom is Fire Elemental and absorbs Fire, but has a glaring weakness of -750% to Ice. The Dad is Ice Elemental and absorbs Ice, but likewise has a weakness to Fire of -750%. Every other element is resisted by 300%. Each parent can act up to 12 times per turn but is programmed to do so only 6 times if their couple is alive.
The Bomb Juniors are the Bosses' spawn and there is one variant for all eight elements. Each Bomb Junior like their parents resist, but not absorb, all elements by 300% except their opposite element for which they have a weakness of -1000%. They have 4,444,444 HP each. The Bomb Juniors can act up to 7 times per turn, but are programmed to act once per turn while either parent is alive.
All of the Bosses are immune to ATK/MAG Breaks but vulnerable to DEF/SPR ones (all Bosses have particularly low DEF/SPR), they are immune to all status ailments, except the Bomb Juniors which can be put under Disease.
Worth of noting, the battle starts with an ambush, the Mom Bomb will spawn a Fire Bomb Junior and a Thunder Bomb Junior who in turn will use a normal attack and cast Imperil.
Mom Bomb Edit
The Mom Bomb uses the following attacks: Exploooding! (Does nothing), Great Explosion (Fixed Type with Fire Magic damage (21x) to all units), Power focused, attack power at 2x! (Increase ATK (100%) for 3 turns to self), Slap (Physical damage (6x) and decrease ATK/MAG (50%) for 3 turns to one enemy), Double Lariat (Physical damage (3x) to all units), The ground is covered in flames: (Add Fire element to physical attacks for 3 turns to all units), Aspir Explosion (Fixed damage (0.3x) as MP drain (30%) and decrease fire and ice resistance (50%) for 3 turns to all units), Mom bomb is screaming (Summon Bomb Junior), Flaming mom bomb exploded (HP damage (100%) with HP sacrifice (100%) to all units).
The Mom Bomb's actions depend largely on whether the Dad Bomb is alive. The Mom Bomb will usually employ physical attacks and spawn Bomb Juniors. She will do this once every 2 and 3 turns spawning random Bomb Juniors. However, every 3 and 4 turns she will spawn a Fire Bomb Junior and a Thunder Bomb Junior respectively, which means there will turns the Mom will spawn two Bombs twice.
She will also use Slap and remaining actions are normal attacks, and Double Lariat every 2 turns provided she has not used Aspir Explosion that turn. Also she will boost her ATK at the end of every turn.
If the Dad Bomb is dead, she will add Fire Element to weapons to the party (she will only do this once per battle), spawn Juniors every turn divisible by 2, 3 or 4, use Aspir Explosion every 5 turns, and Double Lariat every turn Aspir Explosion isn't used. She will use Slap twice with an added chance for a third Slap being used a turn. Remaining actions are normal attacks but as stated above, without the Dad Bomb, the Mom Bomb will act 12 times per turn.
At threshold of 80%, she will use Exploooding!, Great Explosion, Power focused, attack power at 2x! while thresholds of 60% and 40% add Aspir Explosion into the mix. If several thersholds are crossed the Mom Bomb will use as many attacks accordingly, favouring Great Explosion.
Dad Bomb Edit
The Dad Bomb uses the following attacks: Blue Flames (Ice magic damage (21x) to all units), Power focused, magic power at 2x! (Increase MAG (100%) for 3 turns to self), Frozen Flame Shot (fire and ice magic damage (6x) and decrease ATK/MAG (50%) for 3 turns to one unit), Blizzard Bomb (Magic fire and ice damage (5x) to all units), Aspir Explosion (Fixed damage (0.3x) as MP drain (30%) and decrease fire and ice resistance (50%) for 3 turns to all units), Dad bomb is screaming (Summon Bomb Junior).
The Dad Bomb acts as a counterpart to the Mom Bomb using Magic Attacks instead. If the Mom Bomb is alive he will act 6 times per turn, using Blizzard Bomb (if Aspir Explosion isn't used), Frozen Flame Shot twice, boost his own MAG and normal attacks.
If Mom Bomb is dead, it will use Aspir Explosion every 5 turns or otherwise use Blizzard Bomb and an additional chance to cast a third Frozen Flame Shot. If below 50% HP it will spawn two Bomb Juniors every 2 turns. Likewise it will act up to 12 times per turn.
At threshold of 80% it will use Blue Flames and boost its own MAG. At thresholds of 60% and 40% it will add Aspir Explosion to the other attacks.
Bomb Juniors Edit
The most straightforward enemy of the group. Unless both parents are dead it will act once per turn, switching between a matching magic attack of their element to one unit, or cast Imperil (decrease resistance to all elements by 30% to one unit).
Every 3 turns there is a chance to use Bomb junior is trembling (boost ATK 100% for 3 turns to self), and Self-Destruct (Fixed type attack with magic damage of respective element (100x) to all units. And 100% damage to self) the following turn.
The Trembling has a chance of 15% of happening for Fire, Thunder, Wind, and Light Bomb Juniors. Whereas it is a 30% chance for Ice, Water, Stone, and Dark Bomb Juniors.
If any Bomb Junior is damaged but not killed, it will Self-Destruct in that turn. If both parents are dead they will act up to 7 times per turn each Bomb Junior.
Bomb Juniors themselves have a limited stock and can be permanently destroyed during the battle but there are as many as three of each Bomb Junior.
The Battle is rather complex because of the need to use a multitude of elements to deal with all the Bosses. At the very least, Fire and Ice are mandatory to defeat the parent Bombs. Given how the damage formula works when using different elements against an enemy of different weaknesses/resistances, the damage boost (or lack of) will the average of the elemental resistances/weakness along the number of elements involved (simply put if any foe has 100% resistance to Fire and a -100% weakness to Ice and the player uses Fire and Ice damage, then the damage will average to 0 and thus no weakness or resistance will apply at the end).
This can be put to use in order to cover all the different elemental resistance and weaknesses of the Bosses. Realistically, however, it is unlikely the player can cover every element and the damage averaging may harm the player's chances at defeating the Juniors in a single turn (although DEF/SPR breaks may help). Nonetheless being able to cover as many elements as possible is a tremendous benefit.
As such the player is encouraged to finish the battle as quickly as possible. Units with a multitude of element coverage (preferably single-target) will be a tremendous asset. Kunshira and Onion Knight are the best damage dealers for this trial being able to cover several elements amongst them Fire and Water (the former being a requirement against the Dad Bomb and the latter to defeat the Thunder Bomb Junior which is spawned repeatedly), and what's most important, without tying themselves to any elemental equipment.
The player will also need a source for Ice Damage. Fryevia can be useful as she's an innate Ice Damager, the recently released Mediena can work and stack on powerful Ice damage with Zoblizza. The most common way, however, is to use a powerful physical damage unit with an ice weapon, Hyomonto or even Fryevia's Needle work properly for that part.
Defensively, the player is encouraged to use a Physical Cover Tank with 100% Dodge to avoid the parents' powerful physical blow since their ATK cannot be broken and the Mom boosts her own ATK repeatedly. The Dad Bomb provides in another annoyance with unbreakable MAG and constant Fire/Ice Magic Damage, so increasing elemental resistance is required. The Global version has an advantage on Cerius having a Global Exclusive 6★ with enhances that boost her buffs to 100% resistance to Fire, Ice and Lightning for the party making her very powerful for the party. However, because of constant Imperils, the player is recommended to equip at least 30% resistance to Ice/Fire on all their units.
However, before the player can get overwhelmed by too many Bomb Juniors or otherwise to simplify the battle, the player is encouraged to One Turn Kill the parents as fast as possible. Onion Knight and Kunshira can easily perform a powerful Fire chain to defeat the Dad Bomb, although it is still recommended they debuff the Dad's resistance to Fire if possible, decrease his defensive parameters and/or buff their offensive stats. For an easier time, they should push the OTK from slightly above 80% (in order to avoid triggering a threshold retaliation).
The player should kill the Bomb Juniors individually one at a time (as many as possible in a single turn) so as to make the battle load a lot lighter, if chained they can yield a lot of Esper Orbs and Limit Burst Crysts for missions.
With the Dad defeated, the Mom will become more aggressive but with the aforementioned Dodge Cover Tank she will be an irrelevant threat for most of her turns.
OTKing the Mom Bomb is more tricky as typically slotting the likes of Kunshira or Onion Knight means they are ran in pair for proper chaining for different elements leaves only one slot for another damage unit (as the other three slots are for Tanks and other roles). As such the most common way to defeat the Mom Bomb involves a single, powerful damage unit with ice element (equipped or innate) that can defeat the Mom Bomb instantly.
Cloud and Pyro Glacial Lasswell can both achieve this, provided their Limit Bursts are maximized and (preferably) running on a True-Doublehand build, Demon Killers too are also useful. In Cloud's case Omnislash is an instant 21x Physical Damage to one unit, while on Lasswell's his effective multiplier is in essence 15,8x, however if Fatal Bloom's Ice imperil is included, then his damage potential is stronger than Cloud's. Strong ATK buffs may also be needed and a DEF debuff on the Mom to increase the chances of success. Defeating her this way also fulfills one of the trial's missions.
It should be noted, however, that there is a slight complication on OTKing Mom Bomb. Without a strong DEF debuff like that of Onion Knight's maximized Limit Burst, attacks like Omnislash or Unstoppable Wave will fall short of defeating the Mom from either 100% or 80%, which is an additional reason why Onion Knight is such a popular unit.
In case defeating the Mom from the upper tiers of her HP is not possible, the player should slowly weaken her as much as they can but above 50% HP so she doesn't become more aggressive. Given they will break through the 80% and 60% thresholds (even more so if the Dad was defeated beforehand), they will be the victim of Aspir Explosion, so the player should bring items that restore MP and a unit that can restore MP to all the party (If the player does Expeditions regularly one of the items gained there restores MP to all units). Also if the Dad was defeated, the player should be wary of the Fire Element buff the Mom casts. Also and most importantly if crossing thresholds they will be the victim of Great Explosions, which is why Cerius' elemental buffs are so important as they trivialize this threat.
With the proper equipment, buffs and debuffs the finishing strike should deal at least around 22-23 million HP and with Onion Knight's Limit Burst factored in, it should do well over 40 million.
Maritime Strategist Nichol is a tremendous asset because of his powerful buffs and multitude of them (including party-wide MP restoration, damage mitigation for anything not covered, like some Bomb Junior attacks), enhanced Zargabaath is also helpful for it also has potent buffs and damage reduction, both of which facilitate the OTKs and the path to them.
Once both parents are dead the player will be left with whatever Bomb Junior is left alive. The player can deal with them in multiple ways, the most straightforward is to pick them on their weakness and defeat them one by one instantly, otherwise a quick way to wrap the battle can be to use Hide and trigger their explosions. Concealing Cloth can be put to use in order to do that, so the Bomb Juniors suicide while one unit remains alive.
It should be noted that counters may trigger the Bombs to self-destruct, which is why defeating the Bombs along the way is important.All in all this battle puts a significant focus on having access to powerful units and equipment in order to finish things quickly, or otherwise have a long and tedious time. Beating the Trial without high tier equipment or units is possible but takes far longer time, and is notable more complicated, so the player should attempt this battle only after becoming seasoned veterans.