Animal companions have had a long history in D&D. The Animal Friendship spell was not part of the original game, but was introduced as part of Advanced Dungeons & Dragons. This spell was usable by low-level druids and high-level rangers, and allowed the caster to permanently gain one or more animals to act as friends or defenders. Exactly what an animal companion could do was left rather undefined.
Third Edition gave a lot more definition to the animal companion (and trained animals in general). They could do tricks, things like “guard”, “follow”, and “attack”. Rules were given as to how the druid or ranger could command them, and, as far as I can recall it, the system worked. Oh, and there was a lot of magic that could enhance your companion.
In the new edition of Dungeons & Dragons, animal companions have a problem.
It should be stated at this point that there are two ways in the new edition you can have animals accompanying you on your adventures. The first is through the use of the animal friendship spell, which has the potential to charm one or more animals for 24 hours. (I imagine that you lock up the animal for the night, then cast the spell again the next day). This method is available to both druids and rangers, and it’s not entirely clear from the spell whether the animal will actually accompany you or not. You get advantage on checks to interact with the animal, but will it help you? The individual rulings of the Dungeon Master are likely to be quite important here; it will be interesting to see if the Animal Handling skill gains further definition in the Dungeon Master’s Guide.
The other way is to be a ranger. Third level rangers can choose the Beast Master archetype and gain an animal companion that way. This animal gains a bonus to its AC, attack rolls, damage rolls equal to your proficiency bonus, as well as the saving throws and skills its proficient in. It also increases its hit points to four times the ranger’s level, if that’s higher than its normal hit points.
My friend Lewis is playing a 3rd level ranger (beast master) who is accompanied by a panther. This gives it AC 14, HP 13, Bite +5 (1d6+4), Perception +6 and Stealth +8. As we played through Hoard of the Dragon Queen the other day, the group were attacked several times, and he quickly became aware of a problem with the panther: it doesn’t take much for it to be knocked unconscious or even die. It just isn’t anywhere near as resilient as the player characters.
This is going to be an ongoing problem with animal companions. They just aren’t that tough; it won’t take long for them to be taken down by most monsters. The ranger could conceivably use spells like barkskin and stoneskin to improve their survival chances, but the spell that makes a difference – stoneskin – is a very high level spell for a ranger.
One suggestion I’ve heard for improving their survivability includes the use of barding. Frankly, I have trouble with the idea of a panther in plate mail barding, although it seems to be permitted by the rules (although the modifiers to the armour’s cost and weight seem to imply its being used by a horse). My initial reaction is that most animals wouldn’t have a clue what to do in armour and so would suffer the regular non-proficiency penalties until properly trained in their use. However, the rules are somewhat silent on the matter, so in Adventurer’s League play it would appear to be legal. It is also somewhat unclear if the barding gains your proficiency bonus to AC, but let’s say it does. After all, you’re expending a lot of money to get this plate armour on your panther. (Don’t even try it with a bird companion!)
Still, if the animal companion does get hit – or more likely through a spell effect – it’s likely to go down.
Further complicating play of the companion is that once combat begins, it doesn’t do that much. At 3rd level, it can move around, but requires you to give up your action to do one of the few actions it can do: Attack, Dash, Disengage, Dodge or Help. This means that if it attacks, you can’t. At 5th level, when you get your extra attack ability, you can make one weapon attack when you command it to attack. 7th level allows you to command it to Dash, Disengage, Dodge or Help as a bonus action, but only if it doesn’t attack. 11th level is Bestial Fury, so it can now make two attacks, and 15th level spells targeting you also affect your companion.
Of course, there are some really good reasons that animal companions are so weak in this edition. And most of those reasons come from 3E, where animal companions were crazily good; I certainly ran a few games where the druid’s animal companion (a bear) was by far the most effective combatant. Every edition tries to fix problems with those that came before; and sometimes they overcompensate.
Let’s be clear about it: the trouble with the companion is not that it takes an action for it to attack – at many levels, it makes more sense for the animal to attack than the ranger, and once 7th level is achieved, the bonus action to allow it to Help is also really good – but rather that it has a lot of trouble surviving once it’s in combat. That said, that you can buy a mastiff and it may run into combat and attack each turn without you spending a actions to command it (or have your trained mount attack at the same time as you do) leads to a strange inconsistency in play. This may be changed in a later rules update. It should be noted that animals acting independently is up to the discretion of the DM, and it wouldn’t utterly surprise me if a mastiff saw an ogre and ran the other way instead. As it should!
So, you can use an animal companion in combat, but, although its attacks will be fairly effective, it will have trouble surviving. From a game balance perspective, this is probably functioning well – the animal companion is providing you with a buffer of hit points as the monster is not attacking you, but from the perspective of wanting a significant relationship with one animal, it isn’t working so well.
Your animal companion does have other uses; often its perception will be pretty high – although by the rules Survival is used for tracking and not perception, it might be able to warn you about potential ambushes. The degree that it can perform further tricks will generally depend on the kindness of your DM; having the animal as your companion does not grant it any increase in intelligence, although its ability to follow commands already puts it far ahead of regular animals.
Ultimately, the best use of an animal companion will come down to the use of your ingenuity. Items that help protect it should be sought, and it may be wise not to become too attached to the poor, doomed animal! Why were you taking it into the Tomb of Horrors, anyway?