doctorbadwolf
Heretic of The Seventh Circle
Familiars and animal companions have been notoriously squishy. Which is one reason I don't like the idea that they can "help" in combat, but I've never found it terribly fun to get an animal companion, love it, train it...only to have it take a couple bad crits and die...just so that I can then not have a familiar for a like a year AND take some XP penalties. That was FUN. NOT.
Roleplaying out the death of a familiar is great and all, no issue there. And even if it's a spirit taking the form of an animal, it might not want to serve you again if you got it killed. So add a little RP fluff and you end up with the same result, a dead friend who may not be interested in coming back.
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Personally, I really like the way 5E familiars work. Sure, I wouldn't mind an "Improved Familiar" feat or a mildly expanded list (though I thought there was an "ask your DM" list already?). But overall they're a a pet with some special uses that you have to make some effort to take care of. You might not have the materials and time to bring them back!
I’ve been tinkering with a Fey Beast Tamer that takes a familiar and let’s it turn into something that can fight beside you. It started as a Bard College, but I decided that it should be a feat, and I’m trying to make it also benefit BM Rangers. Like, if you have a companion that is a beast with a CR or X or lower, you can apply these benefits to it, and it becomes your Familiar, in addition to its normal statistics and any associated benefits.
So, a wizard with a familiar can have a wolf familiar, and a BM Ranger can turn their much stronger wolf into a familiar that can still attack. It also can be any Fey within the appropriate CR range.
It steps on the Chain Warlock a bit, sure, but multiclassing fighter steps on the Bladelock, they’re pretty minor class features. And hopefully the feat will be useful for Chainlocks.