At level 90, it has a Base ATK of 510 and 41.3% ATK as a secondary stat. At Refinement Rank 1 (R1), its passive increases the damage dealt by the wielder against opponents affected by Pyro or Electro by 20%. Its main highlight is that passive, which serves as a great source of damage bonus when active. So Lion’s Roar is especially good in teams like:

Mono-Pyro Mono-Electro Electro-Charged Burning And Quicken teams where it’s easy to maintain a Pyro or Electro aura on opponents

Its abundance of ATK is also useful but slightly less than its passive. This is simply because it’s easier to get external ATK buffs compared to damage bonuses. And ATK is often a saturated stat in teams that already use ATK-buffing characters, artifacts, or weapons. So Lion’s Roar passive is more valuable than the bit of extra ATK you get from its secondary stat. And in instances where you can’t use its passive, weapons like Amenoma Kageuchi – a craftable 4-star weapon – have a more useful passive than Lion’s Roar. So its value depends mostly on what character and team you’re using. Here’s a cheat sheet of its synergy with all current playable sword users, both with and without its passive active.

Great means that Lion’s Roar is one of the character’s best 4-star weapons options. Good means that Lion’s Roar works on the character, but it’s outperformed by other swords – namely, 4-star craftable, free, or gacha weapons. Not recommended means that the character has significantly better and equally accessible options – or they simply don’t benefit from Lion’s Roar.