Because Dragons are playable for just a short time, the common perspective is that they function mainly as equipment for Adventurers.
Passive Abilities are a Dragon’s most important contribution to combat, since the Adventurers are in play most of the time.
Stats don’t vary dramatically among Dragons, but it’s the main differentiator between Gacha and Event Dragons. Even when they’re the same rarity, max Unbound, and fully leveled, event Dragons lag far behind in terms of HP and Strength bonuses.
Active Skills are considered in terms of status effects, damage, healing, effects, and the animation itself. Some hit a greater area than others, are easier to execute, or provide more useful buffs.
Attack Combos also vary between Dragons.
Finally, availability is factored in. 5★ event Dragons and 3★ Gacha dragons are assumed to be max Unbound, as that is often necessary for them to compare to other Gacha dragons.
These are the most versatile Dragons in the roster, with bonuses that are beneficial to most Adventurers. Most have the maximum amount of Strength available as a passive, while Phoenix earns a place here with exceptional healing.
These Dragons are seen as side-grades to the above Tier 1 Dragons-- Their passives are equal to or greater than pure Strength when paired with the right characters, but are otherwise less effective. Powerful HP Dragons, who greatly benefit healers, are also included here.
Like Prometheus, Gilgamesh is a great value for players who can’t go for the MUB. His offense isn’t as high as Cupid, but 35% Strength and 15% Shadow Res will serve most all Adventurers.
Dragons here are typically either pure Strength or balanced for offense and defense. Most anyone can safely equip these, but neither bonus is as strong as those of higher-tier Dragons.
Being a split-bonus Dragon, Liger falls in the same category as fellow 5★ Nidhogg and Poseidon. He’s strong enough, but with full HP and full Strength Dragons available, he isn’t the best option for either DPS or healers.
Tier 3 Dragons make for solid team options, with moderate Strength and high HP bonuses. Of these, Phantom and Pele are the strongest for damage, while Stribog and Unicorn are adequate on healers.
Although Pele’s Strength boost is lower than Ifrit’s, she does have a good attack-- Blazing Pillars-- which hits the entire surrounding area and inflicts Burn damage. Her availability is limited to those who missed the Loyalty’s Requiem event, but those who got multiple copies can increase her Strength boost and power even further.
50% Critical Damage is a massive boon. Unfortunately, this comes without the means to improve Critical Rate, or the frequency of critical hits. Without a high probability to land Criticals, the benefits of high Critical Damage may never be seen.
In addition, the Light element lacks high-rarity Dagger and Blade users with Critical Rate bonuses outside their Co-Ability, so implementation of Shishimai’s massive power becomes tricky in practice. Assuming a 10-15% Critical Rate with Wyrmprints and Allied Co-Abilities, Shishimai’s damage increase is comparable to a 20-30% Strength buff.
A few distinctions within this Tier: Brunhilda and Zodiark are the most powerful for Strength, while Sylvia and Peng Lai are the best healers. The hatchlings lag behind with their Strength bonuses, but are an upgrade over Drakes, Imps and Fafnirs.
These dragons are typically used as filler on elemental teams. This Tier also includes utility dragons not used for combat, such as Fafnirs.