RTF is a global modification that replaces all towns in the game.

Nephilim look really cool! I personally like these "warriors of death," faceless, in a black cloak. Upgrades, I assume, will get a couple of colored details, blue/pink, like the undead?

The first one will be black with green elements, and the second one will be white with purple, unless a better idea comes up.

Added 1 minute ago
The colored elements can be placed on the swords or parchment.

Added 1 hour ago
We can play with the head model; leave the hood gray, give the unupgraded version a half-decayed head, and give the alternative upgraded version a full-fledged necromancer head with glowing eyes.