It's also possible to fuck your positioning and receive over 300+ damage.
If the duo you're versing is good enough to, figuratively, dodge every single shot and stay out of basic attack range then you've already been hard countered anyway.
Spellthief's Edge deals 10 additional damage. So that's 30 extra damage in a burst of three attacks; like 2 seconds approx.
Every minute Spellthief's Edge can add:
10(1 stack)x6 (Assuming you didn't spend any stacks before an engage) + 30.
That's a total of 90 extra damage depending on spell damage/basic attacks.
Say an ADCs base AD is 50. If the ADC gets to land a basic attack and one after every 10 seconds (matching the support's spellthief passive proc) that's a base physical damage of 350.
Couple this damage to a support's base AD that is 50.
additional 350 physical.
790 total "optimized" raw damage towards the enemy support and ADC.
However you decide to split your damage output between the two. Support against their tanky support and ADC vs their ADC.
Every minute Relic Shield can heal:
40x2 in a few couple of seconds of proccing two relic shield stacks +1 if you count the few moments after the whole minute.
80 (or 120 if three stacks are consumed) health for you and for your ADC. Keep in mind this requires two low health minions half the time you aren't going to have one straight up, might even have to wait a bit more time for the safety of walking up to a minion and last hitting it. Or Spending one of your range abilities to finish one off. Situationally you could get two low health minions nearby after every fight.
Almost forgot, Supports typically save one of Spoils of War for the siege minion. That skews the numbers even more.
However I am aware that if you spend your Spoils of War stacks ASAP by the time you get your 3rd stack of the game the enemy siege minion would be well into the frontlines, assuming your lane doesn't overwhelm nor your ADC attacks the siege minion for themself then you can get a stack off of that. Otherwise the Support isn't optimising their Spoils of War.
120 health back to the ADC who got damaged by the ADC with basic attacks for raw 350 damage.
120 health back to the support who got damaged by the Support with just basic attacks raw 440 damage.
Say the victims have base 25 Armor (for support) and 25 (for ADC).
280 Damage towards the victim ADC.
352 Damage towards the victim Support.
280 - 120 = 160 net loss health.
352 - 120 = 232 net loss health.
With this scenario, you're still out-damaging their heals from Relic Shield without abilities. So no mana wastage. Imagine if I put abilities in. Relic Shield, Targon's Embrace only work to dampen poke not outright negate or even heal off over it.
- There are too many variables to put into one working "global scenario".
Tanky supports typically have strong base health regen but I doubt it can clearly surpass 232 net loss health in a one or two minutes.
You could argue that the damage is less because you can't fit six landing basic attacks in a minute well, I can't be fucked doing this over again m8 and if your support can't proc his/her Spellthief's passive every 10 seconds with either and ability or basic attack then get a new support that one is shite.
These items have been carefully crafted to not be OP or UP. The numbers are not totally off.
**You're over-exaggerating and misconceiving its effectiveness. **