If you don't like big walls of text, this is not the thread for you! Sorry about that.
A lot of people like to complain about heavy armor templars that beam or Breath of Life so I'd like to analyze or explain the situation as someone who mains a templar in both PVP and PVE. For the purposes of the thread, I'll stick to a mostly PVP perspective unless I mention otherwise. In the process, I'll explain why complaining about magicka templars is rather silly and tell you how to easily beat them.
First and foremost, you aren't wrong when you say magplars are great at executing and healing. Those are the two biggest strengths of the class. Magicka templars are obviously excellent healers and make, in my opinion, the best complementary class to pretty much anything else that can deal damage. If I encounter some of the better players in my faction and stick with them, we absolutely clean house. It's so effective, I farmed emperor in an afternoon with a fellow stamplar. If a target has to contend with anyone else, a magplar can really shine with enough healing to let their allies unleash their full offensive potential. At the same time, that templar can wait for the right moment to fire off a finisher via the all-mighty jesus beam. On top of this, templars can easily remove negative effects.
When you look at the weaknesses of the magicka templar, you can understand why stripping away those points of strength would ruin the class. For starters, templars have no mobility. DKs are in a similar boat but their damage absorption, at least on the stamina side of things, more than makes up for it. As for sorcerers and nightblades, they have seemingly unlimited mobility enhancers and escape tools. Templar cleanse is the only way they can stay mobile. I've heard rumors it is going to be given a cooldown, which I believe would break the class without applying a cooldown period to roots as well. If you repeatedly root a templar, they will have to repeatedly cleanse. This prevents them from making offensive moves while simultaneously draining their resources. The templar cannot simultaneously apply offense and defense, save for one spell: Puncturing Sweep. Puncturing Sweep is one of our few offensive spells we can rely on in duels and heavy-pressure situations, but it can be easily beaten by repeated roots, as you cannot pivot the spell direction while rooted. Throw in a stun every six seconds and a templar will be OOM and OOS in no time at all, while being entirely unable to fight back.
Templar sustain is also a joke. This has been the case ever since the early days of ESO, when restoring spirit was nerfed into the ground. To be fair, it was OP to have every spell cast restore 4% of your max magicka, but now templars have to specifically sacrifice offense for sustain more than any other class, making their already clunky offensive spell repertoire even less effective. When I say their offense is clunky, I mean that their spells lack a certain flow or natural rotation that other classes have. When I'm dealing damage as a templar in PVP, I find the spells do not compliment each other and I'm forced into heavily favoring one spell or another depending on the encounter. As mentioned before, roots breaks our bread-and-butter attack, Puncturing Sweep. Then you have Vampire's Bane, a seemingly solid spell that is hampered by the aforementioned lack of flow, among other issues. Dark Flare is fantastic spell for hammering on enemies from a distance but becomes useless in any close situations and duels, where you'll spend most of your time if you're playing in heavy armor, which you should be doing. Dark Flare will hit hard if it hits at all. It is a long cast, is easily interrupted, and comes in the form of a slow-moving projectile that is easily dodged, much like Vampire's Bane.
So at the end of the day, you have far less offensive options as a magicka templar because a significant portion of your spells are ineffective, utility spells, or healing spells. Templars have less options in general with an entire tree dedicated to healing and various other spells to niche mechanics rather than damage output. The few viable options present are easily dodged, mitigated, or otherwise shut down. So in terms of offense, you're left with beams; the only answer to easily-dodged projectiles and easily-countered sweeps. Is it any wonder so many bad templars are beam spamming enemies, even when they're over 50% health? But those templars don't score kills alone because those beams never amount to anything but the wrath of a wet noodle. It's only when those templars have allies smacking you over the head with their stamina sticks that you eventually die to the beam.
I've died to beams maybe ten times over the last several months, with well over 150 hours of PVP in that time. As a magicka templar, I suppose I have more insight into the inner workings of the spell than most people, and I am aware that the best counter to a beam is to heal yourself back over 40% health. I also have the good sense to not whine about a single spell that executes me when I'm dying to zergs of 10-25 players, just because said spell delivered the killing blow. If you die to more than one player, you're likely not a victim of an OP spell but rather a victim of basic math. Two is greater than one and chances are most people can't 1vX well enough to overcome that. If killing blow was the criteria for a spell being overpowered, Mage's Fury is the most overpowered spell I've encountered. That said, I wouldn't mind seeing beams toned down if my other concerns about the magplar were addressed and its general offense became more viable. For the time being, I've slapped my Maelstrom destro staff on and I rely on the player-sticking ultimate to bolster my burst damage to something semi-competitive.
So why the heavy armor? Put simply, light armor sucks. With the stamina meta and no-skill gankers running 2-shot builds, you simply aren't going to have a lot of fun running around without physical resistance. You also have zero stamina sustain in light, which is a major disadvantage for a class with no mobility. You're far too vulnerable to stuns without some form of stamina sustain. Even in heavy, save for perhaps black rose or players who otherwise sacrifice magicka stats for stamina sustain, you'll eventually succumb to well-timed stuns or damage output so high that you either block or die. Even in seven heavy, full impenetrable, and a shield back bar, I find some stamina builds can force me to block or die. This is particularly prevalent in nightblades and sorcerers. You either wear heavy, putting even more strain on your magicka sustain, or you are a wet paper bag trying to stop bullets.
In conclusion, I can see why some people dislike magicka templars and think they're the greatest thing ever. They fill a niche no other class comes close to in their healing and executing abilities, which is fantastic in any group dynamic. What those people fail to see is that the class is not competitive in many other ways and is shoehorned into that role. A lone magicka templar is among the easiest classes to duel against, and arguably one of the least threatening enemies. I've done my best to compensate for the weaknesses of the class and I'm often complimented for my damage potential, but there are still builds I just can't fight 1v1. If you're going to nerf beams, heals, or cleansing, you need to address the shortcomings of the class beforehand. Specifically, more offensive potential in PVP, better flow between abilities, and more mobility. As it stands, it is too easy to shut down a templar's offense, which has led to most magicka templars giving up on damage in favor of taking on a purely defensive role. It's that defensive role people seem to hate the most, because they feel unable to overcome the healing.
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