I have need for these in current campaign - especially the warping effects as the troupe have not been very careful and we therefore have several dozen mundanes (and a magus or two) to assign warping effects (I'd rather do through fun randoms than invent all on the spot).
Before I go and put the effort into putting together something more comprehensive than main rules myself, I was wondering what my sodales have put together or resources I might have missed in older editions, zines, online etc that you might know?
Also happy to get some suggestions here for botch and warping effects (for both mundane and magi).
(most of the warping will be from magic aura and spells, but some from faerie - and a little from infernal).
Dunno about tables specifically for Ars Magica but my friend likes these mutation tables. I haven't picked it up myself or seen it used in Ars but we're using it in the Neoclassical Geek Revival game I'm in and some of the results I've seen were pretty great. The benefit I see of using system-neutral tables is they demand interpretation and I prefer that.
That said, I often feel like it's best to interpret warping or twilight mechanical effects (Virtues gained, spells lost, whatever) somewhat from the events experienced to cause the thing so not sure I'd use tables for anything but a list of example ideas but others can have different views on that and the OSR community definitely seems to love their tables.
First place to look is the RoPM book, i believe a number of their Flaws are listed as 'often coming from warping'. Memory though, since I'm making this post from my phone while getting coffee at work. For non-Magic flaws you can select flaws from the appropriate book.
Also, if you have to get a TON of warping flaws to hand out, I'd suggest just making a short list of sources and assign a few flaws to each source (For example, if two magi are the source of most of the warping, decide on flaws that fit their magical style and hand those flaws out to the mundanes.)
For Twilight Scars for the magi, that's a really difficult one and I always struggle with that.
Since a Twilight event comes from a single source (a discrete event, a particular effect or the botch of one particular spell) I try to link the scars (and the other possible effects like Virtue or Flaw gained) to the effect that caused the twilight and/or the personality/magical proclivities of the caster.
Yeah, I tend to do the same, but when my Flambeaux player went into twilight 4 times during one game session by casting Pilum of Fire in a faerie aura... I ran out of ideas.
Sub Rosa issue 10 has an article on Twilight Scars which I think had a big list in it. Come for the twilight article, stay for the hermetic shipwright and the stormbreaker adventure.