This cantrip seems like it will only delay the inevitable. To cast it takes my action, costing me my ability to to damage. but the trade off is that the enemy would do less if they hit me. So it just seems to slow things down.
I have limited imagination, please help me understand the use of this useful sounding cantrip? Thanks 
xirr2000 wrote:
Does it just grant you resistance to damage? I don't remember the specifics of the spell, but it sounds like it might be useful when you're backed into a corner and clearly overwhelmed, to buy time for the rest of the party to save you.
Eldritch Knight is a big one or if the DM is focusing fire on you for whatever reason and vs creatures with multiple attacks so if 2 or 3 ghouls or whatever are beating on you....
. It is also kind of funny with heavy armor master feat 8 damage becomes 4 becomes 1. 16 damage turns into 8 damage then becomes 5.
It has its uses, it may not be great as such and that is fine for a cantrip.
I think blade ward, along with true strike, are really aimed at the eldritch knight, who can cast a cantrip and make a weapon attack at the same time.
Blade ward is also an option for someone to use when they would otherwise simply use the Dodge action because they have no thing to actively accomplish this turn, but are at risk of being attacked.
For anyone with low AC, it's a better version of dodge, and you would use it the same situations....
When you have cursader's mantle, bless or other quality concentraion spell that you don't want to loose..
When you are blocking a 5' doorway, with alot of enemies in front, and ranged allies behind.
When you have grappled a creature, and are holding.
When you are doing other forms of tanking (sentinal, goading attack, divine challenge, ect).
When you are swallowed, and are at disavantage ot hit and know you will take bludonging damage.
When your going though a trap filled area and you have low perception.
When your about to jump off a cliff (possibly).
When your about to be crushed by an avalanch.
Eldritch knights and valor bards seem most likely, although the bard is more likely being squishier and giving up less attacks. Maintaining concentration is another reason to keep it up, particularly if in melee. The other time would be for expected damage that a person cannot avoid and the action doesn't have a better choice. It seems highly situational so far.
I'll admit that standing there and taking it is typically not the prefered way of handling a combat. However, there are times when halfing your opponents damage is better than attacking.
First, you aren't typically fighting alone. Typically, you are with a party of say three other PCs. You are effectively only giving up 1/4 of your attacks, in return for them doing half damage. If you are a warlock, eldrich knight, or unfortunate wizard blocking an ogre... you might be given up your attack but three other PCs will still be attacking the ogre. Meanwile the ogre's power goes down 50%.
Second, it may still be better than healing. If an ogre is likely to do say 18 hp of damage... that means sometime after being hit a healing is likely to waste an action, move over to you, and cast a healing spell. Blade ward means you only take 9 hp of damage saving at least a healing slot and possibly meaning he won't need to heal you for several rounds -- saving his action(s).
Third, you might not be able to attack. If you are caught in melee with the ogre... you have to use a disenage action to pull back. You can't attack anyway and equally likely your opponent will likely just move up and attack you anyway. Casting ranged spells in melee means a disadvantage and likey wouldn't hit. You might also be blocking the doorway or blocking for other party members and moving back may mean they get slaughtered.
Forth, your attacks might be useless. You are fighting something with resistance, heavy armor, high AC, invisible, etc. Might as well take less damage while some other player with magic, an AoE spell, or magic missile does the damage.
Fifth, you might be intentionally moving through a pile of creature, drawing fire, or otherwise moving to a rear rank. I.e. cast it, and move past several opponent trying to get to say the spell caster at the rear. You specifically know you are trying opportunity attacks or want them to target you. Attacking one isn't that useful. Getting in front of their shaman or getting all their archers to fire at you (rather than your rogue and wizard) could easily be more effective than possibly killing one. This would also work for escape when surounded.
Sixth, you have a lot of other defenses up. For example, someone has warding bond on you, plus you have blur or say heavy armor mastery. You could move into an advantageous position and attacks might seem virtually useless against you. A couple of rounds of that and many opponents might have to rethink tactics -- attack someone else?
Seven, you have some other spell or affect going which is doing damage or effects without you. I.e. you have a web, conjuration, or continuous damage spell up which requires concentration. Maybe better to just stay back and protect yourself while the effect does damage.
However, in most cases, it is better to deal damage than spend your action preventing it. Yet... it is only a cantrip so if you have it and find yourself in a situation where you can't attack, have to block, really need to keep a concentration spell up, etc. its not a bad idea.
Zardnaar wrote:
CCS wrote:
It strikes me as particularly effective for an eldritch knight with only two attacks. If you find yourself in a tight pinch, it could easily be worth it to switch to a blade ward + one melee attack combo for a round or two, hoping your allies will pick up the slack, than just keeping your two attacks each round while being pummeled by a few nasties. Compared to Dodge, you still get a swing in.
Sword_of_Spirit wrote:
You get that power at level 7.
Good replies, thank you all. It does appear situational, but several of you have illustrated many of those situations. Can't see it being used a lot, but it might be one of those spells that alters a fight if used appropriately.
When you are surrounded and about to get hammered, and dont have a better way out.
If youre the intentional tank, and you party is doing great damage while you soak up the half damage hits.
When you are a sorceror and can quicken a cantrip and still cast a normal spell, too
When you know there's a trap nearby and you're pretty sure its about to go off. Same with an ambush, possibly.
If you're a fighter/mage with action surge, or a eldritch knight with the ability to attack and cast in one round.