Spheres are just as important as having the appropriate units. It is important to note that spheres are like equipment in other JRPGs. Equipment is meant to augment your characters' innate abilities. This ranges from doing more damage to surviving better. This concept is the same for Brave Frontier.
The first step that I recommend to do when you are trying to learn about what spheres to use on what units is to learn these two aspects about spheres
Purpose - The reason why a sphere is being used
Function - The actual performance of said sphere
Learning about these two aspects will help you understand why certain spheres are being used on certain units. If you want to know why some of your units are not performing well, it is because the spheres you are using do not fulfill these two aspects.
Learning about Purpose
It is important to know why you need certain spheres to do what you need to get done for any unit. In order to understand, you will need to know about your units and what they do. An example we will use is Cayena. Cayena is a nuker by design so you will naturally want to augment her damage. How do you do so? You will need to use spheres that augment offensive aspects.
Spheres that boost Stats, BB ATK, Critical damage, Spark damage, Elemental Weakness Damage, and etc will help Cayena do more damage overall.
Examples: Armor of Seals, Steeple Rose, Bow of Battles, Annihilator Blade, Snowbound Victory
However, say that you notice some of your units are not surviving well and not getting their bb gauges in a timely manner. Then you will need spheres that will help your units with that. Damage Reduction to help survive and BB gauge spheres to help with your gauges
Examples: Daltisk Phenomenon (BB gauge), Fairy Heart (BB gauge), Daybreak Moon (Damage Reduction), Heaven-Binder (Damage Reduction)
Understanding purpose will allow you to understand why certain spheres are being used. It is also important to note that all spheres have a sphere type and these sphere types generally tell you what this sphere does. There are many types so go to “Unit” then “Equip Sphere”, tap any unit, go to “Sort Filter” then go to Filter tab and you will see the many different sphere types. However sometimes the sphere types are misleading and don't fully explain a sphere.
Learning about Function
This aspect is important because you do need to read a sphere’s effects. Two sphere may have the same type but are actually completely different. It is highly recommended that you look up a sphere on the wiki to check their values and effects.
A general rule of thumb is the more effects a sphere has, the more function it has to you.
Let’s do a simple comparison
Occult Treasure (Status Sphere) - 40% to stats
Beiorg's Armor (Status Sphere) - 40% boost to all parameters, greatly restores HP each turn & probable HP recovery when attacked
So as we can see both of these are Status Spheres but we can see which one is clearly better. Occult Treasure is only 40% to stats while Beiorg’s Armor offers the same amount of stats and 2 other benefits. So in terms of Function, Beiorg’s Armor will perform better than Occult Treasure.
Let’s do a trickier comparison
Blight Arisen (Attack Boost Sphere) - 50% boost to Atk, 100% boost to Spark damage, considerably boosts critical hit damage, greatly boosts BB Atk, boosts elemental damage & lowers Def by 50%
+100% critical damage, +150% BB Atk, +50% elemental weakness damage
Annihilator Blade (Attack Boost Sphere) - Enormously boosts BB Atk, hugely boosts elemental damage, hugely boosts critical damage, 200% boost to Atk & raises max Atk value from 99999 to 200000
250% BB Atk, 175% elemental damage & 150% Crit
So, again we have 2 of the same sphere types but as we can see both have close effects and varying values so how can we tell which one is better? First you need consider all of the effects each sphere provides. Pros and Cons. Then consider which effects are more beneficial to you.
Blight Arisen is basically the jack of all trades attack boost sphere. You get raw attack, spark, critical damage, bb atk and elemental damage. But, it does lower your defense by 50%. On the other hand, the values are lower for some of these compared to Annihilator Blade. Annihilator Blade doesn't have spark damage up but it gives you way more atk, bb atk, critical damage and elemental weakness damage compared to Blight Arisen. It also allows you to break your unit’s atk cap to 200,000 which is another huge boost in damage if you manage to get close to it.
So which one is better?
In my opinion, Annihilator Blade is better. My reasoning is that Annihilator Blade or AB allows your units to hit harder due to the raise of ATK cap. If a unit you are using doesn't have a high break limit then this sphere will allow them to have a even higher attack stat after buffs. BB Atk and Elemental Damge is also more consistent in terms of damage and the values are higher. Even though, there is no spark boost, the other increases make up for it.
Now what if you don’t have the better spheres?
If you are just starting, I don’t expect you to have the best spheres and that’s ok. Many of the top spheres in Brave Frontier are earned after intense grinds in many aspects of the game.
Examples are the 6 Tengi Spheres
Heaven’s Edge - Get Account Level to 999
Sky Orb - Get Thanatos Rank in Arena (max)
Heaven-Binder - Get to Reward Stage 100 in Colosseum
Ragnarok’s Edict - Earn a cumulative 10 million Merit Points
Yggdrasil Edict - Complete 600 Records/Milestones
Daltisk Phenomenon - Frontier Hunter Rank 100
If you can’t get the best now, get what you can and work with it while working towards better.
A recommendation in this current game state is to work on Raid Class 7 spheres as they are
key spheres to have to handle most of the difficult content to the game and the ease
of finding raiders who are willing to let you leech if you can't fully do the Raid effectively.
Learn More about Raid Class 7 by clicking here.