Nehekaran magic is arguably one of the weaker lores in the game. Several spells feel underwhelming relative to the Winds of Magic cost, especially considering that most of them are only able to target 1 unit max, even when overcasted. In most situations the Tomb Kings are probably better served brining one of the other lores available to their faction, especially when damage output is desired. However, the Lore of Nehekara is the only lore accessible to the Tomb Kings with the ability to heal units, and certainly has some other useful utility in addition.
One effective use of this lore is to play cheap and simply. Consistently stringing together casts of the inexpensive Nerus's Incantation and Djaf's Blades spells allows for maximal healing via The Restless Dead, all while constantly boosting units defensively or offensively throughout a battle. One of Khatep's items provides a map-wide buff whenever he casts a spell, which is also conducive to this style.
Brief explanation of each spell:
The Restless Dead combined with the Realm of Souls can keep the infantry of the Tomb Kings fighting for as long as possible.
Djaf's Incancation provides a strong damage boost, but is more useful for the bonus vs. large it grants when overcasted. Overcasting on a lord or character mounted on a Warsphinx allows them to tear apart enemy large units quite effectively.
Neru's Incantation of Protection provides a strong physical resist. Caution should be used not to waste this spell on units fighting enemies with magic attacks!
Ptra's Incantation is useful for ranged units like Skeleton archers, Ushabti (Great Bows), and the Bone Giant. This spell can make them much more deadly and, given that there are a number of Tomb Kings armies that rely on such units, this is a useful but niche spell. Can be paired with Khalida for particularly devastating ranged units, but is still underwhelming overall.
Uisirian's Incantation is a direct damage that slows, rarely sees use and as it is prohibitively expensive.
Uskeph's Incantation provides an area of effect debuff to enemies.
Sakhmet's Incantation is notable for being one of the longest lasting Vortexes in the game. It can shred infantry, but beware its random movements as it can turn back on your own units just as easily as the enemy's.
Trivia[ | ]
Sahkmet's Skullstorm is tied with Flame storm from the Lore of Fire for longest lasting Vortex spell at 27 Seconds (non-overcast).
The Lore of Nehekhara is a lore of magic introduced in Total War: Warhammer II with Rise of the Tomb Kings DLC. It is unique to the 
Tomb Kings race.
