Game Mechanics Ability for Paladin: Saviour

This would be one of the last abilities on the tree, and it is quite simple: If anyone within 20 or so blocks takes fatal damage, 75% of the damage is redirected to you, the saved player gets 50% of their max hp back too, it has a 5 min cooldown for you and a 20m cooldown for the saved player (to prevent multiple save abuse)
Do you think this would be a good ability?

 

This is EXACTLY what I've been wanting as a Martyr replacement

Edit: by exactly, I mean concept wise. Sacrifice your health to save another (obviously you would need more than x% of your HP so it wouldn't kill you or put you in a potentially Fatal situation).

And also 50% does seem insane, it should be like 15-20% at most. Definitely not as powerful as Second Chance since an ally is already getting free death immunity for doing nothing at all.

Edit 2: gonna add some values. For starters, saving an ally from death is already HUGE, so that needs to balanced fairly. Personally, I would say the user sacrifices 40% of their Maximum Health to negate the fatal damage (and to prevent the user from dying, they need to be either above 50% or 60% of their Max Health for this to trigger). Additionally you could give the user immunity for a couple seconds just to prevent them from getting sniped. Also this would need a 20-30m Cooldown to prevent this being triggered twice in raids.

The ally saved should be granted 3 seconds of immunity and have maybe around ~15-20% of their health restored, but all other forms of healing would need to negated during the immunity just so they can't flat out recover all of their health. This let's the saved ally reposition themselves and back off to get to safe location where they can then heal themselves up before jumping back into the fight.

So, what makes this abusable? Imagine a raid full of Paladins (god forbid that ever happens), or even a dungeon run with 2 Paladins. In theory, every player can just negate death for each other and just never die. Remember, saving an ally from death is probably the MOST POWERFUL ability, especially regarding non-raid content. So the user would have to be forced to go full paladin in order to unlock this ability.
Additionally, what happens if 2 allies die at the same time? And I mean the exact same time. Then...I'm not sure. It might have to be a coin toss to decide who gets it.

 

Overall I think it is a really cool ability but I don't think it needs the 50% heal

 

What if you died due to a multihit spell from a mob? It could be 25% then

 

Thats a specific situation, it doesn’t justify an otherwise really strong secondary effect

 

give or take a second of immunity frames should counteract that, no heals at all with about a second of invulnerability should work imo
maybe also a safety net to make sure it only triggers if you're above x hp, otherwise the 75% redirected damage might just kill you which would probably be annoying
overall though its a really good idea, great for martyr thematically

 

bump
give me feedback! is this a good ability?

 

The only change I'd make is, like other people said, only give back a small portion of their HP (10-20%), and maybe give them a second or invulnerability, in case they were hit by something that continues hitting (multihit, arrow storm, etc.) so that they aren't immediately killed again.

 

Didn't feel like making a new post so I added onto my original one