Rule modification to find familiar

A Familiar's Feeling

When an attack would reduce you to 0 hit points, and your familiar can perceive the attacker, your familiar can use its reaction to attempt to interpose itself.

If your familiar is close enough to reach your space using its available movement, roll a d10.

- On a 10: Your familiar dashes to your position and absorbs the attack's damage in your place. You take no damage from a single-target attack. Your familiar's hit points are immediately reduced to 0, causing it to disappear. It must be summoned again as normal using the Find Familiar spell.

- On a 1–9: Your familiar fails to interpose itself, and the attack resolves normally. Your familiar retains its position and hit points.

Restrictions: This feature cannot be used against damage or effects your familiar cannot perceive, ongoing environmental damage, ongoing status effects, or damage caused by you.

Area-of-Effect Attacks: If the familiar successfully intervenes against an area-of-effect attack, you take half the damage you would otherwise receive, rounded down, and the familiar's hit points are reduced to 0. However, if the reduced damage would still reduce you to 0 hit points, the intervention fails entirely. The reaction is expended, but the familiar retains its hit points and position.

I wouldn't make an actual rule for this, and would never use it more than once. If you think it fits the story for someone's familiar to do this at a critical point in the campaign, go for it. But players shouldn't expect this to happen, and familiars aren't meant to be a free 'protect me from death card'. Too many people abuse the rules around familiars as is, why give them anotherr way to do it.

I think that's a great narrative way to allow a familiar to offer a little sliver of hope in a very tense moment. That being said, I wouldn't simply allow the familiar to tank all the damage for an attack, since familiars only have 1 or 2 hit points. If you're down to just a handful of hit points and a fire giant hits you with a flaming sword, there's no way a single-hit-point familiar could tank a hit that does an average of 31 hp of damage. Instead, I would rather allow the familiar to fly up into the enemy's face to distract it, thus imposing disadvantage on that attack roll. It's basically a reskin of the light cleric ability Warding Flare, but with extra steps. That way, maybe the attack misses and you survive. But if the attack hits, sorry, start rolling 4d6 and dropping the lowest.