Okuda is the project manager of the global team for Phantom of the Kill. He is primarily in charge of both overseeing the front-end and back-end engineering, project planning, and illustration teams. He joined gumi as an engineer, and has also contributed to some of gumi’s earlier titles, including titles for mobile web browsers.

One way that we believe Phantom of the Kill is different from other mobile games is that there is an entire story here with a core focus on the personalities of its characters.

Our warriors―the “Killer Princesses” and “Killer Princes”―each have a deep backstory that is revealed over time for players to discover. Additionally, the Killers each have their own unique maturation rates, including randomized maturity level increases, which happen every once in a while.

We had this aspect in mind as we designed a game that you can play for about ten minutes, put it in your pocket, then play a bit more whenever you like and still be able to follow a rich character storyline over time.

Another approach we took from the beginning was to design Phantom of the Kill ‘s gameplay as experience for a portrait, not a landscape, configuration. With most games, you are forced to play horizontally, which essentially cuts out the possibility of playing single-handed. Conversely, although it’s rare to see a game that you play vertically, we saw the benefits of creating one that you could play in this way, allowing you the freedom to hold onto a rail for stability, eat while playing, or everyday tasks.

Mobile Device Design Challenges

If I were to highlight a few issues that came up during the development of this game, I’d start by talking about the nature of developing a user interface for a vertical display. We learned a lot by repeatedly adjusting icon placement. Placing icons close enough together so that they could be reached with a thumb is much more of an involved process than we had initially anticipated.

Larger devices, such as tablets, have varying screen sizes, requiring us to make several versions to accommodate for each of these devices. We contemplated the ways we could create a general user interface, and found one of the most difficult of those endeavors when we attempted to make the game fully compatible with tablets.

(left – before tablet support was added, right – after tablet support was added)

Designing the Weapons and Quests System

Just as in any typical SRPG for console, units in this game grow stronger as you fight with them. Our take on this system is that the weapons these characters wield also strengthen in tandem with these units as they complete each battle.

Those who are already playing the game in Japanese might already realize this, but the global version is much more difficult. We’ve procured a stronger sense of balance to the story mode in the global version, and will deliver new events every week or so. As a feature that remains intact from the original, players can learn how strong they really are while training their units in the colosseum.

This game was made with SRPG fans in mind, regardless of whether they’re guys or gals, in retirement, or just starting school. I dare say that the illustration in this game is magical; anyone who’s into 2D illustrations, visual novels, manga, and anime will be in for a treat when they see the artwork we’ve stuffed into this title.

You can evolve a Killer Prince or Princess by fusing it with materials, maxing out its level, and with zenny, our in-game currency. You can also fuse your favorite units with other units and materials to make your favorite units as strong as possible. Doing this will cause your base stats to boost. Essentially, fusing units before you evolve them is a great strategy, but it will take more effort.

If you’re the type of player who wants to strengthen your units to the best of their abilities, you might want to give unit evolution a shot.

We’re also thinking most quests will last for about five minutes at a time, but if you’re in a quest with strong enemies or are using weapons with advantages and disadvantages over others, those quests might last as long as 10-15 minutes.

Many weapons have merits and demerits relative to other weapons. Units holding axes will have an advantage over units with lances; units holding lances will have an advantage over units with swords; and units with swords will have an advantage over units with axes.

My last bit of advice for players is to start off by accessing the event quests and go through Weapon Triangle Training and Unit Type Training first. You’ll understand the basics of this strategy game very quickly, so I’d recommend you try that out first when the game releases globally.