I like Deltarune a lot more than Undertale. I feel like we're seeing what this combat system can be with a little more experience and polish. Undertale was mostly the box and then a few quirks with the heart being a different color to signal a change in how you moved. Deltarune is moving the box around, rotating it, stretching it out, distorting it, all sorts of cool shit, with even better theming for the enemy bullets. Also the down mechanic where HP can go into the negative, so you can't just immediately revive them next turn if they take a ton of damage, you have to work for that. Smart.

Susie's fun, Noelle is cute, Ralsei is a likable wimp, and then shit, Deltarune's got better boss characters too in The Queen and Tenna.