[Timstone]

The Vorlons and Shadows are two First Ones. The rest are:
- Kirishiac Lords
- Walker of Sigma 957
- Torvalus
- Triad
- Mindriders
- Lorien (the only one left of his race in this galaxy, he is THE first one)

I could also give a full history, but that would require me to type quite a lot and besides it can be found in the books of B5 Wars. I'm not going to type it out, there might be difficulties concerning copyright and stuff.

You aren't very good with names... yeah right... you're giving the whole name, the season and the possible episode number. Sigh...
Now I recall that episode too. I think they just amplified the gravitic field and with that force they tore the Crab apart. Ah well, I'm too lazy to check.
Anyway, in one Version of the stellar map of B5 (in 2258) there are two jumpgates and in another Version there are three jumpgates. Maybe the other Version already took into account the destroyed jumpgate. Who knows...

Edit:
I know about the Centauri selling jumpgate tech to the Humans, but that doesn't negate the fact that the Humans are one of the few races who ever bothered constructing new gates. And that was what I meant.