Heroes with Combat Boosts?

I don't know, I just hope it's not about skills like Earth boost, Fire Boost and Wind Boost

If its what I'm thinking, then things like Earth and Fire Boost, so that means Amelia, Booey, and Luke. But it could also include characters with invisible combat buffs in general, so you may see Hardin, or characters with stance skills, though its not very likely.

At first I actually thought that it would be a combination of drive/spur skills since those give boost during combat, but I guess the actual 'boost' skills make more sense.

The Chinese version called the banner as "Heroes with 'Blow' skills" (not Swift Sparrow or Sturdy Blow, they kinda named it differently to sound different from the regular 'Blow' skills). Not sure which one is correct but either way it doesn't sound like any interesting heroes will appear so... yeah :)