Sorry about if this has been commented on before, but I'm new to the forum, so I'm excused 
When reading about the Master vampire abilities, there is one thing that strikes me. Given that these abilities gives you the option of increasing your units above the starting size, there is one obvious alternative to this: Creating your units large enough to start with. So I started thinking in what kind of scenarios would it be beneficial to summon forces as you go instead of buying them for points. What I came up with was this
Assumtions
If this is the case, then you give one of your vampire one of the 15 point master-abilities (raise XXX beyond starting size and +1 on this casting, 15pts), and (potentially another vampire) the Dark Acolyte (+1 wizard level, 30pts) abiliy. This will give an additional power dice in your magic phase since you're one wizard-level higher. With this extra dice, you cast Invocation of Nehek once each turn. Since you allready tie on your opponent in the magic phase, you will have all his dispel dice tied up with dispelling your other more usefull spells, so this will never get dispelled (or your more usefull spells can be cast without interruption, a gain either way). Since you only have one die, the spell will succeed on a 3 or more (remember the +1 on casting), or 2/3 of the times. For each succesfull cast, you will summon D6 new wounds worth of units or on average 3,5 wounds of units. Depending on your choice of mastery you will summon bats, wolves, ghouls or skeletons. Your best choice here is the Fell Bats which is worth 10 points for each wound, second by skeleton w/spear at 9 points for each unit. This all sums up to summoning on average 3.5 * 0.666 * 10 = 23.3333 points worth of units each turn. Given that the cost of this combo only cost 45 points, you'll have a expected net gain allready by turn 2. Even when summoning lesser units like skeletons or ghouls you'll have a net gain by turn 3 - measured in points. Note that you are here only using the extra die you got from increased wizard-level to cast this spell, so you don't loose anything you didn't have before exchanging your units with the abilities.
There is several effects not noted here, but allmost all of them will augment the effect seen here. If your opponent choose to dispel your summoning, then your more expensive spells will have a higher chance of getting cast. You could include a corpse cart in your army which would increase the expected raised units. If you allready had planed to cast invoctaion of nehek, then you now got +1 on casting which would improve your rasing still. If you got 50 points of unused vampire abilities you could choose Master of the Black arts (+2 power dice, 50pts) which would give you extra power dice at the cost of 25 pr dice instead of Dark Acolyte(+1 wiz lvl, 30pts) which costs 30 for each extra die.
So the moral of the story is that if you can keep your choice of summoning regiment and the vampire wielding the chosen powers alive for 3 turns, then it will always be beneficial to remove 45 points of starting units and exchange them for the above vampire ability combo.
When reading about the Master vampire abilities, there is one thing that strikes me. Given that these abilities gives you the option of increasing your units above the starting size, there is one obvious alternative to this: Creating your units large enough to start with. So I started thinking in what kind of scenarios would it be beneficial to summon forces as you go instead of buying them for points. What I came up with was thisAssumtions
- You got a total of 45 unused vampire points to spend
- You allready dominate or tie in magic prowess during your magic phase
- Usefullness can be measured in points
If this is the case, then you give one of your vampire one of the 15 point master-abilities (raise XXX beyond starting size and +1 on this casting, 15pts), and (potentially another vampire) the Dark Acolyte (+1 wizard level, 30pts) abiliy. This will give an additional power dice in your magic phase since you're one wizard-level higher. With this extra dice, you cast Invocation of Nehek once each turn. Since you allready tie on your opponent in the magic phase, you will have all his dispel dice tied up with dispelling your other more usefull spells, so this will never get dispelled (or your more usefull spells can be cast without interruption, a gain either way). Since you only have one die, the spell will succeed on a 3 or more (remember the +1 on casting), or 2/3 of the times. For each succesfull cast, you will summon D6 new wounds worth of units or on average 3,5 wounds of units. Depending on your choice of mastery you will summon bats, wolves, ghouls or skeletons. Your best choice here is the Fell Bats which is worth 10 points for each wound, second by skeleton w/spear at 9 points for each unit. This all sums up to summoning on average 3.5 * 0.666 * 10 = 23.3333 points worth of units each turn. Given that the cost of this combo only cost 45 points, you'll have a expected net gain allready by turn 2. Even when summoning lesser units like skeletons or ghouls you'll have a net gain by turn 3 - measured in points. Note that you are here only using the extra die you got from increased wizard-level to cast this spell, so you don't loose anything you didn't have before exchanging your units with the abilities.
There is several effects not noted here, but allmost all of them will augment the effect seen here. If your opponent choose to dispel your summoning, then your more expensive spells will have a higher chance of getting cast. You could include a corpse cart in your army which would increase the expected raised units. If you allready had planed to cast invoctaion of nehek, then you now got +1 on casting which would improve your rasing still. If you got 50 points of unused vampire abilities you could choose Master of the Black arts (+2 power dice, 50pts) which would give you extra power dice at the cost of 25 pr dice instead of Dark Acolyte(+1 wiz lvl, 30pts) which costs 30 for each extra die.
So the moral of the story is that if you can keep your choice of summoning regiment and the vampire wielding the chosen powers alive for 3 turns, then it will always be beneficial to remove 45 points of starting units and exchange them for the above vampire ability combo.
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