In Sunday's post about expanding Holmes Basic, Gameblog reader Gratuitious Saxon Violence (one of the best handles ever, by the way) suggested that all characters gain +1 to-hit every three levels and that superior Fightery could be represented by giving the Fighters an extra attack at the same time. I like that a lot. It's very straightforward.
An analogous situation is the Magic Missile spell, which gets more missiles at higher but the details are unspecified. The easy answer is that Magic Missiles work just like Fighter attacks. You get a second Missile at 4th, a third at 7th, etc. A more ridiculous way to do it would be to roll dice. You get d4 missiles at 4th level, d6 at 7th level, d8 at 10th level, d10 at 13th, d12 at 16th, etc. Sounds excessive but I kinda like the idea of high level MU's raining craploads of magic arrows down on people. Especially when in Holmes you have to roll to-hit for all those missiles, something I made a mistake about when running last Wednesday.
I've also given some thought to the eighteen listed but undefined 3rd level MU spells. Rules for some of them can be found lurking elsewhere in the text:
Fire Ball - have this spell work exactly like the Wand of Fire Ball (i.e. all Fire Balls do a flat 6d6 damage)
Fly - functions just like Potion of Flying
Haste Spell - just like Potion of Haste
Hold Person - as per 2nd level Cleric spell Hold Person
Invisibility 10' - as per Invisibility, but area of effect like a protection scroll
Protection/Evil 10'- as per Protection from Evil, but area of effect like a protection scroll
Infravision and Water Breathing are pretty simple to do. All you really need are a duration and number of creatures affected. I'd probably default to d6+6 turns, just like standard Holmes potion durations. Is there any real reason to grant the effect to more than one person? I'd extrapolate from spells like Levitation (caster only) or Invisibility (caster or one target).
Monster Summoning I gives you one roll off the first level wandering monster charts, creatures appear and obey caster for d6+6 turns, then leave. I might limit this spell to dungeons only. Rather than appearing anywhere in a puff of smoke, these guys just come from around the nearest corner or through a handy door. At the end of the spell they go back to watching TV or playing tiddlywinks or whatever.
(Speaking of dungeon-only spells, you know what else would be a better spell if limited to just the underworld? Continual effing light.)
Slow Spell is the opposite of Haste. Half moves and attacks every other round. No big whoop.
Dispel Magic is mentioned in the text of a few other spells (as a way to negate Hold Portal or put out Continual Light, for example). Should it be limited to countering spells that specify it in the description or be more general purpose? It could cut both ways. For a campaign setting with a lot of techno-magical crap you probably don't want a single madman (e.g. an standard PC) to be able to bring your civilization down by running around casting dispel on all your lightning trains or undead vending machines or whatever. For my more pseudo-historical/The Magic Goes Away flavored game, I think it would be neat to have the PCs erasing everybody else's free standing miracles.
So for my game Dispel Magic ought to have a chance to undo pretty much all spells (including negating attack spells as they are being cast), magic items and even things like golems. I'm thinking the base chance of success could be 50% plus the MU's Int score and level. Note that the level of the caster of the original magic does not figure into the formula, as I hate having to stop the game to try to figure out who the heck wizard locked the ancient treasure chest in room 24.
It's pretty obvious that Lightning Bolt is an attack spell. Should it work like the wand-based magical attacks, doing a flat 6d6 damage, save for half? Should it have an area of effect. My gut instinct answers are no and no. The area of effect of a L-Bolt has never sat well with me. I see it as an unnecessary artifact of the miniatures origin of the game. In my mind's eye a lightning bolt zaps just one target, unless metal conductivity is brought into play. As far as the damage output is concerned, I think the lightning bolt could do less damage, say only 3 or 4d6 but no save for the damage. Instead the target must save or be stunned for d6 rounds. Failure to save would also indicate the target is smoldering and covered with cartoonish black scorching.
Those are the easiest spells. I'll tackle Clairaudience, Clairvoyance, Explosive Runes, Rope Trick and Suggestion in another post.