Ouch. That's a good combo. Between the two, it might just be worth using swords dancer over sentinel for sheer damage and speed. No account for survivability though. I still maintain swords dancer should be anti infantry, not anti building.
It fits the flavor more, as something that cuts down foot soldiers with ease. Buildings aren't taken down by unpredictable, fast movement as dancing with twin swords. In fact, I've wondered how swordsmen in general get a bonus vs buildings, but it doesn't bother me too much except for this particular one. A sword will bounce off a stone wall lol
I think it is mostly like soldiers raiding a place. I've always been bothered more of arrows that bring down buildings lol xD
Anyway the real problem about the unit is not a matter of bonus but the fact that whirlwind attack was meant do deal damage like a normal attack (growing with techs effect) instead it deals like 4 attacks.
Anyway i don't think a high bonus against infantry would be balanced (it could take down 4 at times without receiving a counterattack). I would give it more a bonus against ranged units (that aren't expert in swordfighting). Thanks to its mobility it might be easily put in the middle of archers killing a good number at once.
Well, I know a little in d&d 4e. The teleportation mechanics there are easily handed out with the right equipment, race, and classes. One race that is closely related to elves, eladrin, has a natural ability to teleport 5 squares (25 feet ish I think) with only a 5 minute rest to recharge. Several items give a similar ability, and one pair of boots even let's you teleport anywhere in sight up to a mile, once a day. Swordmages have a number of teleportation abilities that let players almost never have to walk.
In short, it could easily be explained as utilizing either inate magic or specialized equipment, or some combination thereof. Done this way, it might be reasonable to expand the concept to other elves we want to add it to later.
Might need a new name though. And I don't think the ai will ever use it as more than a speed boost. Not that some players will do differently.
Generally teleport is something used by high level mages but in 3.5 editions there are some classes in a book called tome of battle. Those classes use KI to power up their magic-like feats. Some techniques can also stop time, so I assume we might give it a martial flavor.
So I guess our options are magical, equipment based, or monk based. Honestly I think I like the equipment route, for having elf smith research it. Maybe even make this the first of a sub-category of techs there, starting with an "enchantment" tech that allows you to research a variety of abilities or upgrades, including this one. That helps build a tech tree by adding a technology to research further technologies.
What about boots of enhanced jumping or Boots of dislocation?
I'd like to stick with the original jumping idea since sworddancers are the agile kind of warrior and a leap and slash action it would be more fit for them.
The ninja style dislocation (ki based) might also fit but a magical teleport is out of their flavor in my opinion.
Researched at elf blacksmith for 3 turns, requires you to research "enchanting" for 6 turns.
Yes, this totals 9 turns for 1 upgrade right now, but later enchanted equipment will add small 3 or so research cost options, merely making the first tech a small barrier to a variety of related options that are cheaper because of that initial input.
Cant you use siege tower mechanic? Also I think its a good think too add,I would want to use it in AoU and also flying units in all games should be able to pass throught enemies thought.