So for someone like myself, who never played 4th Edition: what does the "Warden" do that the Oath of Ancients paladin cannot do with the right feats and spells? Serious question, not trolling.
Well, let's see.
Wardens in 4e were, as stated, very "sticky." They were very, very good at keeping enemies locked down where the Warden wanted them, which usually meant "next to me, because I can take the hits." Stickiness is difficult to achieve in 5e in general for a variety of reasons, but you might be able to kludge something together, especially with UA and a DM open to favorable options (e.g. bringing back Marking and allowing non-Reaction OAs when opponents violate the mark.)
Wardens, like most Primal characters, tended to have absolute gobs of HP (most Primal classes had Con as a key stat, either prime or secondary, and tended to get more baseline HP per level, with the Warden getting more base HP than any other class in 4e.) This is theoretically doable with the Tough feat, but...well, that's honestly kind of a dull feat so it sucks to have to take that.
Wardens specialized in
not wearing heavy armor (they had features vaguely like Unarmored Defense that only applied while wearing medium or light armor.) There are no 5e Paladin features which particularly support wearing medium armor, unfortunately.
Wardens called on the powers of the land itself to do damage. Some Earthbender-type stuff (due to one of the initial builds being "Earthstrength"), though they had no singular elemental affinity. Things like calling on spirits of thunder or physically zooming around the battlefield like a hungry predator.
The biggest thing though, at least for my money, was the Warden daily powers. Almost all* Warden daily powers were "Form of X," where X was some super thematic natural thing, which would give you (essentially) a stance effect for the remainder of the encounter. Notably, these powers all had the "Polymorph" keyword. This means they actually do
physically transform the Warden while active. Each one would give some sort of significant effect, often changing terrain, making zones, or otherwise altering the world around the Warden--hence the emphasis on "stickiness" at the start, because by locking enemies down near herself, the Warden was very good at forcing enemies to deal with whatever Form she had manifested.
Here's an example of a 1st-level daily Warden power:
Form of Winter's Herald.
Daily ✦ Cold, Polymorph, Primal
Minor Action | Personal
Effect: You assume the guardian form of winter's herald until the end of the encounter. While you are in this form, you gain a +1 bonus to AC and resist 5 cold. In addition, each square within 2 squares of you, wherever you move, is difficult terrain for your enemies.
Special: Once during this encounter, you can use the Form of Winter's Herald Attack power while you are in this form.
Encounter ✦ Cold, Polymorph, Primal, Weapon
Standard Action | Close burst 1
Requirement: The Form of the Winter's Herald power must be active to use this power.
Target: Each enemy in the burst
Attack: Strength vs. AC
Hit: 1[W] + Strength modifier cold damage, and the target is immobilized (save ends).
Miss: Half damage, and the target is immobilized until the end of your next turn.
For clarity, powers have a common format for the header:
<Type> ✦ <List of Keywords>
<Action> | <Range>
"Attack" defines the stat used for the bonus and the defense targeted (the options being AC, Fortitude, Reflex, or Will, which are static defenses on the target, not saves the target must roll.) "Effects" always occur, unless the text gives a reason why they shouldn't. "Special" things are additional characteristics or features which only apply under certain circumstances. "Resist N <type>" means you ignore the first N points of damage of the given type(s) from a particular action/source. (If the damage has multiple types, you must resist all of them to have resistance apply.) Note, I have cut out the fluff text at the head of the power, though all powers have such text between the name and the mechanics.
Notice how this power affects the Warden herself (+1 AC and resist 5 cold) as well as the world around her (difficult terrain in a 2-square--aka 10'--radius.) Further, her attack immobilizes an opponent no matter what, but that effect is stronger if she hits.
Past the early levels (that is, by level 9 or higher), this is the kind of thing a 4e Warden should be doing a couple of fights a day, every day. There's...really nothing comparable to this in the Paladin, be it spells or class/subclass features. The closest thing is their
capstone ability, which they don't even get until 20th level, and that's
once each day. You can kinda-sorta kludge something out of a few of the Paladin's aura spells...but nothing that says "nature" pops out at me from the spells I can see. Even the closest semi-examples require 3rd or higher level spells.
*The only exceptions are at level 5 and 19. Not really sure why those got the more "smite-y" kind of powers, but hey, it's what they are.
