As there are always numerous questions as how to level a certain class and not all class guides on the official forums or on fan websites offer help of how to actually level your character talent, stat and ruby grid wise I will collect some good information about how to raise your new summoner to 40.
There are numerous builds for 40 out there but most often they lack a walkthrough description of the way to 40. Of course there are numerous and valid ways to reach your final build and resetting your talents is common once you reach the final level to build the build that suits you best.
My offers here are mainly about a Vamp/DoT build which I find the most versatile.
Here is a link to the final build I am slowly approaching to:
Again this is for level 40 and not yet for level 42.
I did not use all the rubies and there are especially talent tree wise a few options to maybe reconsider.
I will now go through the Talent Tree part I think are the core options for every Summoner:
Your bread and butter DoT. Part of almost every rotation. No need to hurry it to rank 3 though but the first talent points should be spent there to unlock the next talent row.
As a cloth only class you want every little piece of additional armor you can get. The power of Blood Aegis is dependent on your perception so the higher your perception the higher the armor gain through blood aegis. And you want rank 3 for the additional armor bonus, the additional charges are nice but not the main reason for ranking it.
Unless you want to go a fiend or lurker route later on get this to rank 3 as soon as possible. It will do most of your damage, tank for you, short: The hellion is your best friend.
I cannot comment much on a non hellion build as I never tried it but I imagine leveling with a low rank hellion or no hellion at all must be hell - no pun intended.
Quite a few might disagree with me here but fear is just too good to not have it on a low cooldown. Both in PvE and espcially in PvP you do not want enemies to get to you. To fear them away is the best way to keep them off you. Remember that summoners kill slowly but surely we do not have a lot of burst dps so fear is a good way to be safe until your DoTs wore the enemy down.
Your single target HoT. It heals quite well costs only one blood and can be precasted. I would recommend rank 2 but this depends really on your healing preferences. Some prefer to have reanimation instead at a higher rank.
The spell that makes the summoner. This spell is causing the most controversies about being OP or not within the community. Its long duration of 60 seconds combined with its infectious nature and - depending on gear - high ticks of damage are what make people complain about summoners. If there is no healer close or the enemy has no spell to dispell or mitigate it somewhat you can often see your enemy following you into purgatory if he finally got to you.
There are other skills that are recommended and good to have like
Plague of Mending (Rank 1-2):
This spell is the only instacast heal a summoner has and therefor quite useful. It is infectious but produces antibodies which prevent to be infected for a while after you got infected. Still a strong and useful multiple target heal spell.
Reanimation (Rank 1-2)
A nice "Oh No!" heal which can heal your whole HP in one shot. Needs to be either precasted or its cast time reduced with proced skills for reducing cast time.
Rise from the Dead (Rank 2-3)
Rank 3 with its 5 min cooldown is the best "Oh No!" spell the summoner has. In PvE it saves quite a few holy charms and I am almost thinking of moving it to the "must have" skills. It is just that wandering fever and rise from the dead both at rank 3 make it difficult to change a lot of the lower tier skills as you need to spend all your talent points on the last tier once you unlocked it. Therefore be careful with your talents if you want both fever and rftd at rank 3.
Volatile Infection (Rank 1-2)
Summon Soul (Rank 1)
But non of these I see 100% essential and it depends on your playstyle what you want.
For stats I recommend putting them all into luck. Luck on gear is often a single stat and you do not want to have too low luck which means you actually sacrifice other stats as e.g. perception most often comes in combination with faith.
Keep in mind that Allods is very level and stats based. A single level makes quite a big difference and higher stats are the thing to look out for. This also means that you should try to get all the reputation respected gear available as this really boosts your power quite a bit.
also keep in mind that the summoner is a caster class. This means its power comes mostly from the used wand and not the equipped weapon. There is no need to look at the DPS of a staff, if a combination of dagger and off-hand provides better stats go for this. And always try to have the wand with the highest magical power equipped.
At endlevel besides the gear high level runes also make a huge difference now. High level runes are pretty expensive to get so though, both with in game gold and via the cash shop.
One thing I will likely try to change from the lvl 40 build I posted above is to drop Vampirism to 1 and get Volatile Infection to 2. I will also drop Summon Soul and with the additional 2 talent points from level 41 and 42 get Dark Renewal to rank 3.
Ruby wise that build should have Necropotency at rank 3 as the instant cast of Dark Renewal is just too good to be not available regularily.
Additional rubies can go into Cold Eye or Healing Shield or whatever your preferences and playstyle likes. I went for Healing Shield as it is nice for kiting.
Now let's continue with the actual leveling guide:
This is pretty easy.
As you likely do not know whether to have an Acid or Vamp build and both build types will rely heavily on DoTs anyway just rank Putrefy to unlock the second talent row where you then get the Hellion which will help you a lot for the beginner island. At level 6 a lot of people take Blood Injection - well I did too on my character but would not do so a second time - to have the first heal spell. I recommend saving the talent point and rank the Hellion to 2 at level 7.
Now of course you can take Blood Injection if you want to heal and want to have it just for the fun factor. However if you go to a Vamp build you will likely never use Blood Injection anymore once you get Dark Renewal at around level 18. If you run low on health I suggest buying some food from the quartermasters if the Hellion runs low on health just resummon it. I do not think that the reduced downtime with Blood Injection - come on 10 seconds downtime from recasting the Hellion which you can recast in combat as well - is a good reason. The fun factor is though. If you like to party up and heal your party members then take it but keep in mind you will not be using it after level 18.
This is still pretty straight forward.
Talent tree wise we maxed out our Hellion and it is the real fighting machine at this point. I started to build Blood Aegis which gives you additional armor. While you will not notice it that much at that level because your Hellion is really strong and will do all your tanking Blood Aegis becomes really important later on.
If you have the level 10 rep gear and have some decent perception you should not need to worry much about leveling and killing mobs.
For the ruby grid we are heading towards Corrosive Acid on the Acid Bolt grid.
On the way there we will pick up Blood Tap which returns you some blood after killing mobs and also return to some mana making nullifying the need for mana potions completely.
Why do we go to Corrosive Acid first?
Well it helps your Hellion to hit harder, parties like that you reduce the mobs armor so that the physical hits on the mobs hit harder and this all helps to keep the aggro off of you.
Possible deviation: Do not take Blood Aegis yet as you might already know whether to head Vamp or Acid build then you could level one of these skills to 2 at level 11.
Now we have Corrosive Acid and you should immediately see how much easier your Hellion takes the mobs down.
Talent tree wise there is not much to say as Putrefy got to rank 3 and Blood Aegis to rank 2.
If you already decided to go for a Vamp build you could also rank Vampirism to rank 2 instead of Blood Aegis. Generally you might want to keep Vampirism at rank 1 overall so that you have a bit more options later on.
If you choose a different talent tree road make sure you test it in the calculator before to see when you can finally get Dark Renewal. This is also the reason why I chose Fear which we will then rank to 2 to get access to the next talent tree row
Also note that at this point you can still spec for an Acid build if you want to.
But soon the paths of these two builds will fork.
Possible Deviation: If you already went for either Acid or Vamp you will likely have less Blood Aegis but I recommend getting it soon now.
Talent tree has no Fear level 2 and Dark Renewal level 1.
I also went to get the first two intelligence booster rubies to help both your spell damage and your Hellion's physical damage.
Once you get Dark Renewal you might want to start working on a bigger blood bank which is the last ruby for this build and probably the first where the roads of Vamp and Acid build actually forked.
In the talent tree we just made our HoT a bit stronger and also took Summon Soul to be able to raise a dead friend and save him the trip to the purgatory and the fear of death effect. If you do not play in groups a lot then you will not cast this spell very often but it is always good to have it. Rank one is totally sufficient. As the Gipat patch took out the Fear of Death effect you might want to save this talent point for something more useful later on as you will get another 2 talent points for levels 41 and 42 giving you the possibility to maybe get the 3rd rank of another talent.
In the ruby grid we now head for our next DoT which also has a great CC effect by stunning the target after a few stacks have been put on the target: Neurotoxin.
Neurotoxin you can cast once on the target and more stacks will automatically be put on the target but you can speed this up by spamming Neurotoxin on the target. For now it is quite a low cost spell so you can spam it quite a bit.
After Neurotoxin it is worth to invest a bit into the stamina rubies for you and the pet. We also prepare to take Howl of Death like this which is a great CC and damage spike spell but it costs a lot of blood so we need to build some proper blood bank and blood income first to make it really useful.
At this point you likely will not need much help anymore as you should have quite some experience with the class already. We have now at least the first rank of endless blood and howl of death.
The next steps should either be get another level of endless blood or go towards debilitating plague.
The way to debilitating plague is always part of discussions but I find Panic Monger much more useful. First you can easily re-apply DoTs as they are instacast and the small additional mana consumption is not that much of an issue usually. Second you might not need fear that often but once you need it in PvE the cooldown seems always too long e.g. if you aggro 2+ mobs then those few seconds can easily mean life or death.