Level 1 M-U
This is used to bind a creature to the caster. No creature will be bound willingly by this spell, for even the most domesticated animals will be afraid.
The kinds of creatures allowed will vary by campaign. What is important is to remember that the higher the HD of the creature, the more difficult it will be to keep bound.
Once a type of animal is agreed upon by both player and GM, a gift to the targeted creature must be made. The more exotic, wild or magical the creature is, the more costly and rare the tribute. Once the creature has been lured into the caster’s proximity, the spell is cast.
The targeted creature is allowed a saving throw, adjusted at +1 or -1 for each level/HD of difference between the HD of the creature and the caster. Thus, a 1HD Toothsome Bunny would be at a -3 save vs. spells against a level 4 mage. The HD of the creature is adjusted upward by one for each special attack or spell-like ability the creature has. If the creature saves, it immediately attacks the caster or runs.
If the creature fails its save, it is bound to the caster. The caster permanently sacrifices 2 HP for each HD of the familiar. These HP are permanently added to the new familiar’s total. Familiars take on some of their master’s personality and a bit of their intelligence, so they gain +2 to saving throws and will generally not be caught or harmed due to general animal ignorance.
A familiar can perform small tasks, such as carrying written messages, guarding spellbooks or “retrieving” items from other players. It can whisper information to its master and can be given simple commands, including commands to go places where its master has been or find people he knows.
It can telepathically send along what it sees, hears and smells and hears from up to 200 feet distant. Its master must concentrate to receive the message. It cannot receive telepathic commands or impressions.
Some familiars are willing to engage in combat, particularly wilder animals. When attacking much larger/powerful enemies, they must pass a loyalty check (see below).
No matter their intelligence, familiars can be trained to perform tricks beyond what others of their species can learn.
Small familiars may be kept in the sleeves of a robe or under a hat. Others might require a cage or to be allowed to roam or fly freely.
If a familiar somehow ends up in combat against its master, it gets +4 to hit and does double damage.
Once per week, and in certain situations, familiars will make a loyalty check. 2d6 is rolled and modifiers are added or subtracted. The following table is then consulted.
Loyalty Check Result:
12+ The familiar is fanatically loyal (or powerfully bound) and would follow its master to the end of the world. Add +1 on next loyalty check.
10-11 Familiar is quite happy with (or resigned to) the relationship and will willingly do what it can, short of self-sacrifice.
7-9 Familiar is well-disposed toward (or afraid of) its master.
5-6 Familiar will do what it is told, although it may be stubborn or ornery about it.
3-4 Familiar is unwilling to do as told, but if threatened, will comply (although the job might not be thorough).
2 Familiar has disappeared for a week (at least). -1 to next loyalty Check
Below 2 Familiar will attempt to betray its master, get him killed or otherwise break free of magical bond (Choose one, make a saving throw vs. spells, no modifiers). Penalty of -2 on next loyalty check.
Familiars are best kept loyal through humane treatment and/or disciplined treatment. But because of the power of the binding spell, they are more easily swayed into loyalty by improved or more disciplined treatment.
A lap cat or a well-trained hellhound are equally loyal. Likewise, an animal kept in fear might remain loyal to a point. Level difference and other modifiers make the most difference.
The DM should of course determine which modifiers apply in each case and even which animals are effected by which sort of treatment. A cat, for example, might respond well to indulgence, whereas a horse might not.
Loyalty Roll modifiers
For Casters level – Familiar’s HD: + or – 1/2
Daily Training: +3
Stern but humane treatment: +3
Affectionate Treatment: +3
Inhumane or Cruel Treatment: -2
Well-fed by hand: +2
Given freedom to hunt and roam: +1
Per HP Damage taken in combat: -1/2
Per combat where familiar is attacked but not hit: -1
For each other familiar master has: -3
Per month left behind or with someone else: -1
Per day in extremely hostile climate or environment: -1
Per year with master: +1
This something I’m throwing out there for comment. I have no idea when I’ll be able to test it in a campaign. Probably 2011…
[Note: edited for typo and clarity.]