Awakened Worlds CE

There are a lot of reasons for the non-awakened to be leery of magic. Perhaps the biggest one is that spellcasting is not obvious, especially when the spellcaster is invisible. A perceptive runner will notice when a potential adversary aims a firearm or baton at you, but your first indication of offensive magic may be when you start bleeding out of your ears.

Flipping the roles around, what this means for the spellcasting runner is that in cases where adversaries are not aware that they are in fact adversaries, you can often take the time to knock out each member of a guard detail with stunbolts staged to deadly as they won't understand that you are the one attacking them.
NOTE: Spellcasting alone does not initiate combat, meaning it does not put you in initiative rounds. Outside of initiative, you have a half second delay (IRL time) between spells.
NOTE: Technically, a target that takes damage does understand that they are being attacked, but if the damage is staged to deadly, they don't get the chance to react (unless they have a trauma damper or pain editor).

While manabolt and powerbolt deal physical damage, stunbolt deals mental. This means that using stunbolts, a spellcaster needs to deal twice as many boxes to mortally wound a target, by filling the mental track and then overflowing through the physical track. However, stunbolt has the advantage of lower drain. Spell drain codes are calculated as (F/2 + modifier)(drain level), i.e., casting a stunbolt 6 at deadly has a drain of (6/2 - 1)(deadly) = 2D. Let's take a look at the odds to completely resist the drain for stunbolt, manabolt, and powerbolt, all cast at force 6 and deadly, compared to drain resist dice (willpower + spell pool). A trauma damper does make this significantly easier.

Another attack spell that is often recommended is waterbolt. While stunbolt/manabolt/powerbolt are direct combat spells, waterbolt acts more like a firearm - it can be dodged and armor applies (though at half impact instead of full ballistic). But unlike stunbolt, it can be used against turrets, drones, and vehicles. [Khai - can powerbolt target turrets, drones, vehicles?]

Improved invisibility is probably the most desired (or hated, depending on who has it) spell in the game. But for runners, there is a bit of nuance to using it. If the invisibility is seen through by any means, guards will respond aggressively. While a force 1 stealth spell can be used to prevent auto-detection via ultrasound, astral perception or the rare lucky spell resistance roll will still be able to spot you. In addition, if you initiate combat in a way that does not immediately knock your target unconscious, they will fight back even if they can't see you. Once somebody is fighting you, they can also alert others who cannot see you and so you can end up fighting everybody in the room (and possibly also adjacent rooms). There are a number of autoruns that will go smoother if the subtle runner does not use invisibility.
For the not-so-subtle runner, improved invisibility is a very potent buff, as adversaries who are fighting you but can't see you suffer a +8 TN blind fire penalty. If they have ultrasound, they suffer a penalty of (8 + the force of your stealth spell)/2 (round up), max +8. That said, it's not a stand-alone solution; if you don't have the dodge or melee dice, then they can still luck into landing the occassional hit, and without soak and armor, a hit with just a single net success can still do a lot of damage.

Unlike a shaman, a hermetic mage's spells are limited by the quality of their library. There are no sorcery libraries with a rating greater than 8 available in Awakened Worlds CE. That restriction causes hermetic attack spells to be very unreliable when facing off against certain top tier opponents. Example: a force 8 stunbolt with 24 dice vs 16 willpower gives less than 4% chance of success, whereas a force 12 stunbolt in the same situation gives a 20% chance of success.

Where the hermetic has the advantage is their elementals, which have the ability to sustain spells associated with their element. A shaman is not able to sustain the various beneficial spells (beyond what can be handled by the available force 3 or 4 sustaining foci) without having to deal with prohibitive TN penalties in subsequent actions. Thus, a hermetic is better at using their magic in a self-supporting role. Along with the weakness in offensive spells, it makes sense for high-tier mages to approach situations they find dangerous in the same way as a street samurai (i.e., shooting large firearms loaded with APDS from outside the room).
NOTE: Elementals cannot sustain health category spells.
NOTE: A mundane street samurai can reach rating 12 with firearms and melee skills and so is generally better at killing (except when opponents are spirits/elementals). A hermetic with a full suite of buffs plus spell defense / reflecting is generally better at surviving (even more so if willing to pick up some cyber/bioware).
NOTE: In a team situation, a shaman is better at support magic, as they can sustain force 12 spells on teammates while the hermetic is limited to force 8. While the shaman would take sustaining penalties, that doesn't matter when teammates can be relied on to handle the action.

Ritualcast now enables buffing with automatically maximized successes. The following dice optimization considerations are only applicable if you're buffing up by casting normally.

The effectiveness of most sustained spells is from the number of successes you achieve, where the force only serves to cap the number of successes you may use (notable exception: armor). So, it's common for spellcasters to recast such spells until they reach that maximum number of usable successes. This leads to the question: how should you split your spell pool between casting and drain resistance so as to both maximize your chance of reaching maximum effective successes while also minimizing your time spent recovering from drain?
NOTE: Drain power is calculated from half of force (round down), plus a modifier and damage level depending on the spell.
NOTE: Heal/treat spells and biotech treat work on physical drain damage.

This depends on too many details to explore here. That said, when outside of combat, you can cast a spell every half second, so let's take a look at how many drain resistance dice (willpower + spell pool) it takes to have around a 90% chance to not take any drain, i.e., around 10 attempts per rest. Let's also aim for enough spellcasting dice (sorcery + spell pool + foci) for around a 10% chance of hitting the effective successes cap. These numbers assume the caster doesn't have a trauma damper. A key result is that you need much less dice if you're willing to aim for a result that is slightly less than the absolute maximum.

• In character generation, spell points should generally be used for spells. Once in-game, learning spells takes significantly more effort compared to picking up the karma to bind foci or buying conjuring materials.

• In character generation, spell points should not be purchased at 25k nuyen per point. For the purpose of bonding foci, 1 spell point = 1 karma. For the purpose of learning spells, 1 spell point = 1 karma + convenience of not having to find/buy/design the spell formula (and access to a sorcery library). For the purpose of elemental materials, 1 spell point = 1k nuyen.

• Melee is defended against by melee, so pick up a melee skill.

• Keep the illegal stuff holstered/sheathed/put away until you actually need them (NOTE: this includes the improved invisibility spell!). That way, if they're not already aggressive, you can just knock everybody out with stunbolts without entering combat.

• Because drain codes are calculated from spell force divided by 2, rounded down, it is more efficient from a drain perspective to cast spells with odd number force.

• Trauma dampers do apply to drain, which is very much worth it despite the bioware index penalizing your magic rating. Being bioware, it doesn't affect your essence and so it doesn't penalize the essence dependent spells that you might wish to cast on yourself (e.g., heal).

• Speaking of essence dependent spells, the mud does allow you to use a decrease attribute spell to reduce the TN for an increase spell for the same attribute, after which you can release the decrease spell.

• It is perfectly ok to use elementals (and thus sustained spells) at less than max force. Summoning force 5 elementals instead of force 8 will result in 2.4 times as many services (on average). Force 5 elementals also require fewer conjuring materials, so in total, you'll be able to support 3.8x as many spells for the same amount of nuyen. Just force 5 combat sense (with 10 spellcasting successes) and force 5 armor are enough to put your combat pool and armor ratings on-par with or better than most street samurai.

• The odds of a mundane elite guard beating the spell resistance check vs a force 5 imp invis (with 5 spellcasting successes) is 9%. This means if you know you're walking into a fight, go ahead and cast that (and sustain with a water elemental) because it means at least 9 out of 10 will suffer TN penalties against you (+2 to shoot/melee/dodge if astrally perceiving, at least +4 if ultrasound, +8 for everybody else). Against force 6 (with 6 successes), their odds of beating the spell resist check is 0.04%.

• Autorun Johnsons ignore stealth spells (as well as invis spells). The stealth spell also does not cause guards to aggro, so it's perfectly ok to keep it active at all times. If you use the stealth skill, the spell makes it much less likely for opponents to beat the perception check. NOTE: sneaking works when moving between rooms; stand in a room long enough and opponents will spot you without needing a perception check.

• When fighting against high force spirits, allocate your spool to defense/reflecting and use a weapon focus.

• For dangerous high-tier fights bring a large firearm loaded with APDS and shoot in from outside the room.