How much does mixed clear and difficult terrain reduce movement?

Question

The rulebook states:

A character's Water Ring is considered two Ranks lower (to a minimum of one) for the purposes of determining how far he can move using Move Actions when on difficult terrain. [...]

This is all well and good, but leaves a bunch of edge cases open to interpretation. In particular, what happens if difficult (or moderate) terrain only covers part of the area you were intending to move across?

By way of example, four samurai are competing in a footrace over uneven terrain. Each of them has Water 4 and so can normally move 40 feet in a Simple Action. Each of them takes a Simple Action to move.

• 1-san's path is completely clear. He moves 40 feet.
• 2-san's path is covered in thick bushes. He is considered to have a Water of 2, and so only moves 20 feet.
• 3-san's path is almost completely clear, but there's a small thicket of undergrowth right in front of him. Even though he will only be moving through it for ~5 feet, does it still reduce his effective Water to 2 for the entire move and so cost him 20 ft of movement?
• 4-san's path is like 3-san's path, except the patch of bushes is 25 feet away from him. If trying to cross it were to reduce his Water to 2, he wouldn't even be able to get far enough to reach it in the first place (and presumably would therefore be limited to 25 ft of movement as entering the bushes would mean moving beyond 20ft). Is this correct?

Optimally, an answer would point me to a section of the rulebook I have missed, errata, or a statement from the developers.

Answer 1

You'd need to make some judgement calls here, but it might be best to identify the how much movement per square each square takes up.

As you said: Water4=40', Water2=20'. (1/2). So just assume 40' of movement with each square of difficult terrain counting as 10' instead of 5'.

3- he would move 10' of his 40' over the one patch of difficult terrain, then be able to move the extra 30'.

4 goes 25' of 40' then uses 10' to get through 5' of bushes (35 used) then can go 5 more feet.

Answer 2

In its core, L5R 4th was marketed as "L5R your way". A lot of the rules are written deliberately in way, that they are open to interpretation. So there is no hard and fast rule for your problem, but there can be taken a case for both ways.

1) if your movement is reduced at any point of your move, then you suffer the full reduction. 2) you only suffer the reduction for the part of your movement, that moves through the inhibited squares.

While it is never stated explicitly, all the movement stats are given in increments of 5', which coincidentally overlaps with the well known dnd rules and the many battlemaps available. So, while I never played L5R with a battlemap, you have all the tools to do so and are even encouraged by some of the rules to do so (the +5' for a full attack springs to mind).

So, by taking our inspiration from the dnd rules set, I would opt for option 2). In the end it is entirely your call.