"Improved Share Spells"

[Sahansral]

Quote from the PFSRD

You can share spells with those you have a magical connection with.

Prerequisites: Spellcraft 10 ranks, ability to acquire an animal companion, eidolon, familiar, or special mount.

Benefit: Any non-instantaneous spell (but not any spell-like ability) you cast on yourself can also affect a creature bonded to you (such as an animal companion, eidolon, familiar, or special mount). The creature must be within 5 feet of you at the time of casting to receive the benefit. The spell’s duration is halved between you and your bonded creature (for example, a spell with a duration of 1 hour has a duration of 30 minutes for both you and your bonded creature).

If the spell or effect has a duration other than instantaneous, it stops affecting the creature if it moves farther than 5 feet away from you. It does not affect the creature again if it returns before the duration expires. You may share spells in this fashion even if the spells normally do not affect creatures of that type. This feat only applies to animal companions, eidolons, familiars, or special mounts gained through a class feature.

So, can you share touch spells like Calcific Touch or Chill touch with your familiar and let master and familiar attack with this spell at the same time?

When spells with a limit are shared like Protection from Energy, does master and familiar have a shared limit or two seperate limits? Another example would be Call Lightning which limits the total number of lightning that can be called.

Or to paraphrase it, fore some spells doubling the the number of targets and halving the duration is roughly equal in power. For other spells you nearly double its damage output, absorbed damage etc. Hard to estimate the intended power level of the feat.

[avr]

You can share touch spells, buff spells, whatever. For some spells this has a greater effect than others, yes. Where limits not based on duration are concerned I think those are shared too - the text suggests one spell affecting both. It's not totally clear though and an ask your GM situation.

[Dragonchess Player]

Sahansral wrote:

So, can you share touch spells like Calcific Touch or Chill touch with your familiar and let master and familiar attack with this spell at the same time?

No. You do not cast either spell on yourself; the target of the spell is "creature or creatures touched," not the caster.

Quote:

When spells with a limit are shared like Protection from Energy, does master and familiar have a shared limit or two seperate limits?

That's the GM's call, but I'd probably have separate limits like communal protection from energy.

Quote:

Another example would be Call Lightning which limits the total number of lightning that can be called.

Like calcific touch and chill touch the caster is not the target of the spell.