[3.5] Shadowdancer- how to dip effectively?

[Lateral]

Exactly what it says on the tin. How can I take a dip in Shadowdancer most effectively (1 or 2 levels to net supernatural HiPS and possibly Evasion/DV/UD)? Is it ever actually useful?

[Flickerdart]

Yes. Shadowdancer has the best HiPS of any class. The 2nd level usually isn't worth it because it's so easy to get all those abilities much earlier. Taking it any further is silly.

There is an armour enhancement that grants Mobility, I believe, so you don't need to waste the feat. Since all three prerequisites are Fighter bonus feats, something like Feat Rogue 2/Bard 3 nets you almost all of the prerequisites (and also Uncanny Dodge and Evasion so you don't need the second level) and gives you room for 2 more class levels of your choice (which can be Feat Rogue too, giving you another bonus feat).

[Curmudgeon]

Getting into Shadowdancer is an expensive proposition. Starting as a Rogue you can handle the skill rank part of the cost, but the feats are tougher. So here's what you do.

1. Consider a Dodge replacement with some other benefits. With a high movement rate you might do well with Expeditious Dodge, for instance.
2. Buy Mobility as an armor enhancement which grants the feat (see Magic Item Compendium). Note that you can have armor enhancements without actual armor; see Arms and Equipment Guide about adding such to Bracers of Armor.
3. After you take your first level of Shadowdancer your next feat should be Spring Attack. Just as Shadowdancer has expensive requirements, so does Spring Attack ─ but you've already paid for them to enter the prestige class. This gives you an acceptable return on the investment. Against most enemies you'll use Hide in Plain Sight to Hide while making full attacks. Against foes with good Spot skills you might not be able to overcome the -20 penalty to Hide while attacking, so you will Spring Attack (and Hide without the -20 penalty), attack, and then move (and Hide again).
4. If you want to take level 2 of Shadowdancer (to pick up darkvision, perhaps) you'll need to have done some adjustment to your Rogue abilities to avoid duplication. I like the Spell Reflection Alternative Class Feature (Complete Mage) to trade evasion for the ability to reflect spells targeted at you that miss; and Uncanny Bravery ACF (Dragon Magic) to swap uncanny dodge for improved resistance to fear. (This complements the Craven feat very nicely.)