Skills
When leveling up you will get some skill points which you can use to unlock some useful skills. This can be done in the Skill Menu.
How to open the Skill menu:
Press P (Check your key-bindings) to open the Vampirism menu and then press the Skill menu button
Skill points
Skill points are awarded each level. Without modification, you will get 14 skill points (-1 for the initial skill) When you become Lord you can acquire additional 5 skill points.
More Skill points
More skill points can only be gained by changing the configurations.
There are tree ways of doing this:
Unlock all skills on max level
Therefor you must edit the allSkillsAtMaxLevel option in the server config to true.
Get multiple skill points on levelup
Here you can increase the skillPointsPerLevel value in the balance config.
Install Vampirism Godly
You can install Godly Vampirism, it automatically increases the skillPointsPerLevel value.
Actions
Some of these skills will allow you to use "Actions", if you have unlocked one (e.g. "Regeneration") hold R down and keep it pressed.
A "skill rose" will pop up, move the mouse in the direction of the desired skill until it's highlighted and release the button. If you don't want so select any skill either release the mouse when nothing is selected or select the red cross.
I can really recommend you to switch the key binding to the middle mouse button, because it is a lot easier to use, but conflicts with the Vanilla pick block.
All skills have a cooldown time, you can only activate it if it is not in cooldown mode. Some skills also have a duration, then you can deactivate the skill if you do not need it anymore by selecting it again to decrease the cooldown time.
Faction specific Skills
Lord Skills
Minion Recovery
Reduces the time minions require to recover after they die.
Lord Movement Speed
Grants Movement Speed to nearby entities of the same faction with lower level.
Lord Attack speed
Grants Attack Speed to nearby entities of the same faction with lower level.