At level 90 Refinement Rank 1, it has a Base ATK of 542 and a secondary stat of 44.1% CRIT rate. It does have a relatively lower Base ATK than most 5-star polearms, but this is compensated by its really high CRIT rate. So it’s especially good for units that use multiple external ATK buffs (like Xiangling) or don’t scale entirely from ATK (like Hu Tao). Additionally, its passive also offers a bit more ATK to its wielder. This passive is called Heat Haze at Horizon’s End, and it has the following effects:

Increases the wielder’s ATK by 52% of their Elemental Mastery. When their skill hits opponents, the Dream of Scarlet Sands stack will be gained for 10s, up to 3 maximum stacks. Each stack grants the wielder an ATK bonus that’s 28% of their Elemental Mastery.

This passive is especially good for units that benefit from both ATK and Elemental Mastery. And for units that don’t benefit from its passive, it’s still a great CRIT rate stat stick. To help you out, here’s a cheat sheet of Scarlet Sands’ synergy with all current playable polearm users.

Great means that the weapon works well with the character, and it’s one of their best weapon options. Good means that Scarlet Sands works on the character because of its high CRIT Rate stat, not passive. Not recommended means that it doesn’t synergize well with the character – or there are significantly better options (usually 4-star or 3-star weapons).