Expansion and customization of powers

[Azgarm]

In the Powers chapter there is a box that says:

"The Scope of these Rules

These powers are adapted from prior Chaosium, Inc.
games (see the bibliography in Chapter 12: Appendix). They
are not all-encompassing: expansion and customization
is encouraged. These are a foundation with which you
can create additional new powers or adapt them freely
from other sources such as movies, books, or even other
roleplaying games."

In the Magic section says:

"If a magician is trying to invent a new spell, discuss it with your
gamemaster."

In the Sorcery section says:

"You and your gamemaster may choose to
create additional spells or modify these are you see fit."

The question here is that I want to be a Gamemaster and I don't know how either.

How do I do it?

Thanks in advance.

 

[NickMiddleton]

You need two things: in game mechanisms for these things to  come into existence (how does a character create a new spell?) and gm rules guidelines for novel items that fit with the rest of the system.

There are rules in Magic World  for researching new spells, and it’s supplement Advanced Sorcery significantly expands the sorcery spell list (MW & UGE sorcery are the same).

Otherwise, I am not aware of any formal rules: the best advice I can give is to carefully examine the existing rules and look for patterns, obvious omissions and inclusions. There are no “teleport” type spells in sorcery for example, and few if any spells like D&Ds Fireball & Lightning-bolt. Spells that fit the patterns of existing spells should have similar costs and requirements; spells that do not should be carefully consider - adding them changes the feel and tone of the system substantially. If that’s intended, all well and good; but be wary of unintended consequences!

The same approach applies to all the power categories in UGE: be guided what already exists for the scale, scope and cost of new powers; analyse the existing material for obvious patterns and styles; evaluate novel additions carefully for the consequences of their inclusion, intended or otherwise.

[g33k]

Nick gives good advice.

I'd add one more element:  whenever you're in doubt as to "how costly" a spell/effect should be, or "how potent" -- err on the side of less-powerful (higher MP cost, lower damage, slower to cast, etc etc etc).

Because
 #1 It's far far easier to give a player/PC more power, later...  if  it seems you were too-conservative; taking power away is often unhappy-making!  Retcon with "as you settle in to the new power/spell, you figure out small ways to leverage a bit more out of it," if such retcon is needed.

 #2 As per Nick's point about "unintended consequences" -- overpowering a caster can turn them unexpectedly (and unwantedly) dominant in a mixed party.