The Ashblazing Grand Duke

The Ashblazing Grand Duke is a Relic Set in Honkai Star Rail that is very useful for characters who deal damage through their Follow-Up Attacks. However, it's not ideal for every character specialized in this type of damage.

The 2-piece bonus increases the damage of Follow-Up Attacks, which is straightforward. Regarding the 4-piece bonus, the in-game description can be a bit confusing, so let me explain it briefly.

For each hit a Follow-Up Attack from the wearer lands, we'll gain a mark. This means that if your character's attack deals damage in multiple ticks because it hits several enemies or because the attack itself hits multiple times, we'll gain multiple marks. The more marks we have, the more attack bonus we'll get, up to a maximum of +48%.

What does "This effect is removed the next time the wearer uses a follow-up attack." mean? Well, the effect itself lasts for 3 turns, but each time our character performs a Follow-Up Attack, the number of charges will reset. The idea is to equip it on characters whose Follow-Up Attacks hit many times, ideally also hitting in an AoE, so we can maintain the maximum number of charges 100% of the time. Topaz & Numby don't hit in AoE with their Follow-Up Attacks, but Numby hits many times, so this set is indeed good for her.