I have a Scout/Ranger character (human, now 15/1) and it works great. It’s not really optimized, but for me it’s a lot of fun. It requires tactical thinking and a backup plan though.
However, this advice requires the following options from outside the book selection in the original question:
- Swift Hunter feat (Complete Scoundrel, p. 81): it allows stacking Ranger and Scout levels for the purposes of skirmish (Scout) and favored enemies (Ranger). Also, it allows to apply skirmish damage to creatures resistant to precision damage if they are your favored enemies.
- We have house-ruled the second part (overcoming resistance to precision damage) to a separate feat (“Greater Swift Hunter”) to satisfy DMs reservations.
- Improved Skirmish feat (Complete Scoundrel, p. 77), extra dmg and AC bonus with more movement.
Greater Manyshot feat from Psionics. It’s not a psionic feat though:
When you use the Manyshot feat, you can fire each arrow at a different target instead of firing all of them at the same target. You make a separate attack roll for each arrow, regardless of whether you fire them at separate targets or the same target. Your precision-based damage applies to each arrow fired, and, if you score a critical hit with more than one of the arrows, each critical hit deals critical damage.
- Again, we have removed the option to use it against multiple opponents (as ridiculous). You can use it in your negotiations with your DM. Usually, you’d want to deal all your skirmish damage to a single enemy anyway.
For this build, Ranger levels are not essential (you really only need Ranger 1), so the multiclassing restriction works against you. I assume you are level 3, so taking the first level in Scout will already set you back -20% XP. Ask your DM for some leeway - to remove the penalty, to make Scout your favored class or to allow for a larger level gap.
Levels and feats
Main Scout advantages (in the context of the question):
- mobility (+10 ft. movement)
- higher initiative
- uncanny dodge
- Tumble (class skill)
- flawless stride (like Ranger’s Woodland Stride, but any terrain)
- bonuses to AC
- BAB 3/4
- precision dmg not always applicable
If you cannot take Scout only (I assume you are level 3 Ranger now):
4 Scout +1 DEX
6 Scout Swift Hunter feat
7 Scout Improved Skirmish (you meet the prerequisites thanks to Swift Hunter)
8 Ranger +1 DEX
9 Ranger Improved Initiative or something for your “backup plan”
11 Ranger (Manyshot from class)
12 Scout Greater Manyshot, +1 CON?
- Efficient Quiver - you will need to be able to draw exactly right bane arrows.
- Bane arrows - you need a variety of bane arrows, for most types of enemies. Establish with your DM that you can buy bane arrows in small batches (fractions of 50). 50 +1 bane arrows cost 8302,50 gp.
- Gloves of Dexterity (the stronger the better) - you need your attack bonus.
- Potions or scrolls (if other PCs will use them on you) for buffing your attack bonus.
- Something to improve your CON…
- To improve damage you could consider Skirmisher Boots (Magic Item Compendium, p. 136) - they are cheap, allow extra attack (single arrow, not Manyshot) and should not bother most DMs...
Examples for levels 6/7 and 12/13. Note that damage average doesn’t account for chance to hit: high mobility of the Scout makes it easier to select targets and go for lower AC opponents (spellcasters!). At the same time it doesn’t account for critical hits.
Some minimal assumptions for Level 6/7:
- favored enemies are assigned +4/+2
- bow +1
- gloves of dex +2
- potion of Heroism (attack +2)
If shooting bane arrows:
Attack bonus: BAB +5 (L6) or +6 (L7), +1 point blank, DEX +5, bow +1, bane +2, Heroism +2 = +16 / +17
Damage: 1d8 + 2d6 bane + 2d6 skirmish + 2 (bow/point blank) (+ favored) + 2d6 improved skirmish (L7) = 20.5 average (L6) or 27.5 average (L7)
Note: it may seem you get similar results with bane arrows and Rapid Shot (or maybe better for Rapid Shot against favored enemies), but considering your low HP, additional mobility and AC bonus from skirmishing give you more tactical options. Use Rapid Shot whenever profitable though.
Some minimal assumptions for Level 12/13:
- favored enemies are assigned +4/+4/+2
- bow +1
- gloves of dex +4
- scroll of Greater Heroism (attack +4)
If shooting bane arrows:
Attack bonus: BAB +10 (L12) or +11 (L13), +1 point blank, DEX +7, bow +1, bane +2, Heroism +4, manyshot -4 (L12) or -6 (L13) = +21 (L12) or +20 (L13)
Damage per arrow: 1d8 + 2d6 bane + 3d6 (L12) or 4d6 (L13) skirmish + 2 (bow/point blank) (+ favored) + 2d6 improved skirmish (L7) = 31 (L12) or 34.5 (L13) average
L12 - 2 arrows = 62 average (or 70 for most favored enemies)
L13 - 3 arrows = 103.5 average (or 115.5 for most favored enemies)
Tumble maxed out. You need it for tactical movement on the battlefield. Remember that Disable Device is a class skill for the Scout (see Complete Adventurer errata).
As for many precision-based-damage classes you need some backup plan - my character usually carries some alchemical fire (“improved”), holy water, smoke sticks, figurines of wondrous power, feather tokens etc. Or simply a torch.
Other things to consider:
You get some class features twice - evasion, trackless step, woodland/flawless stride. Consider negotiating with your DM to replace them with something else. Or use them to convince him that switching to Scout is not really a multiclassing….
Obviously, you can optimize the Scout further with access to other sources.