Death

Unfortunately when you die (usually from doing something really dumb like casting your most powerful spell on yourself to see if you can survive it) the story ends there. No second chances no continues that's it.

However your successor can take up to 4 or your runes depending on how far you got and use them in the next game.

Upon dying you will get a short message followed by being told what killed you and a score (if you care about that kind of thing).

You will always be able to choose at least 2 runes for your next game when dying however if you get to level 5 this will increase to 3 and if you reach level 10 you will be able to pick 4 runes (this is the max). Sadly enough, completing the game will prevent you from passing any rune to your next character. When picking runes think which class you are going to play as and how useful it will be to that class. Also bear in mind how long the rune will be useful for. A rune which uses a lot of flux may not be as usable for a low level character as it would be for a high level one.

Picking a combination of runes that work well together can be great and can start your new character off with a very powerful spell. Artifacts can be good choices but don't feel you have to pick all the artifacts. You can pretty much guarantee that if you kill every enemy you will find the artifact you are looking for at some point in the next game. This can make the +10 Power +50% modifier non artifact rune much more rare and valuable.

That said bringing an artifact back isn't such a bad idea. Apart from the advantage of starting with a powerful artifact it also means that if you kill the monster that would usually drop that artifact they will be forced to drop a different one. For instance if you kill the Farmer and take horde and die and restart. If you kill the farmer again he will drop a different artifact. If all the artifacts in the game are in your possession they will start dropping random runes.

How not to die:
First off it's a good idea to note that the game is pretty stingy with death. If your hp reaches 0 at any moment in the game apart from the tutorial then it counts you as being dead - even if your hp was just about to go up again. This can make a big difference when lots of different status' are in effect as the order of when each damage hits you will define whether or not you died.

List of turns:
Regeneration>Poison>Burn?>Your Spell if Cast>Enemy>Cloud>Movement if you moved

As you can see Poison and Burn actually hit you before your turn starts and any healing or attack clouds hit you last of all. This means that if you are poisoned and and you don't have enough hp to survive the poisoning you cannot just cast a heal spell. If you do so the poison will hit you first and kill you before you get to use your move - it will result in a 0hp situation and you will go to gameover screen.

To beat poison or burn from killing you on the turn the only way to beat it is to cast a regeneration spell powerful enough to add enough hp onto you to counteract the poison. Cloud is way down on the list so if you were relying on healing clouds know that you will be hit by Everything else first before the cloud heals or damages you.

Staircases:
When you go up a new staircase you don't have to fight everything. You can retreat down the staircase again and try again. Also if something is chasing you that you can't defeat try heading down a floor.

Don't make spells bigger than your own head:
If your main spell does more damage than your max health you may want consider either downgrading it or increasing your constitution. It's probably only a matter of time before you cast it on yourself and die by accident. if you're using a spell which with a fixed area of attack that doesn't hit you then this of course doesn't matter as the spell can never hit you.

Read the spell description:
This one should be a given but it's so easy to just relax especially when you get to later levels and start destroying everything and begin to experiment with even more powerful spells and not read what exactly what they do. Easy mistakes to make for instance would be while powering up your healing spell even more you start replacing your runes in the spell with even more powerful ones ... only to find you didn't read the description and removed all of the defensive runes from the spell - and it killed you.

How much flux does the spell do? How much flux do you have? Is attacking that block you made with 100 turns worth of poison counter really a good idea? Be wary of status spells.

Beware of Powerful status:
This one is easily overlooked. If you are using the status Powerful to get a lot of damage you need to remember a couple of things. Firstly it will eventually run out (unless it has negative turns). Secondly Powerful increases all damage that you do. It really does increase all. This includes spells you have set deliberately to 0 damage to remove helpless status. Artifacts that feedback damage to you will do more damage to the target and feedback more to you. Healing spells will do more healing your melee attack will do 2 + Powerful. Quake will start vaporising the room and you as well.

Don't fight battles you can't win:
Low hp, high flux tons of dragons? Maybe it's time to retreat. You don't get any prizes for taking on huge numbers of enemies at once. You can always scope out a new enemy with the z key and get a huge amount of information about them.

Plan ahead:
Have you made a healing spell? Do you have a plan for if one of your spells goes wrong? If you accidentally cast 50 turns of burn on yourself do you have a way of removing or surviving it? Not having healing spells is actually sometimes a problem - sometimes the game just won't throw any defensive spells your way. This can make even the really bad ones useful.