Exploration

Always remember that during Build-Up, black space is your main resource. Black space is mana and is health. And you will transform that health and mana into damages, experience, objects... for the final fights.

So don't be shy in exploration, but explore wisely (easier to say than to do, no ?)

Monster regeneration

Keep in mind that monsters regenerate while you are exploring (1 HP per monster level). So you will often want to fully heal/recover mana before starting a fight.

Or, in some case you will be able to damage a monster quicker than it heals (regen-fighting), but in the end you would have had to hit it more often, and would thus have used more health. So, keep in mind that it is less efficient in terms black space. So make sure that the bonus XP is worth black space usage.

Spare mana/health usage

If you wish to fully recover before a fight, you will often have more health than or vice-versa. It would be silly loosing it, so always try to use the spare health/mana for something. There are plenty of opportunities to invest spare mana (monster slowing, giving burning effect, getting physical resistance from wall crunshing,...), so make good use of them. Spare health might slightly trickier to invest wisely as monster will heal at the same time as you do. But before fully recovering mana, you can also double check that you really need it !

If you can save all mana/health, don't worry too much. You often won't have a choice or have something to do.

Black space positioning

You will sometimes need to explore just 1 or 2 squares during a fight, to recover the right amount of health to give the final blow, without allowing the monster to heal too much. So it is always a good idea manage such accessible black tiles during your exploration.

Exploring the inaccessible

There will often be tiles which can be explored by normal means. You can still exploit them with LEMMISI (explores random tile) or BLUDTUPOWA (explores nearby tiles). Destroying walls is another way to reach them.