http://leagueoflegends.wikia.com/wiki/Seraph%27s_Embrace
http://leagueoflegends.wikia.com/wiki/Gold_efficiency


20cdr*26.667gold=533.33gold
1400mana*1.4=1960gold
21.75gold per AP* (2400mana*0.03+50) = 2653.5gold
1061gold from AP when build deathcap
mana passive 2400mana*0.333refund*1.4gold = 1118.88gold


Cost 3200gold


so you pay for cdr+AP
and you get the value from mana and deathcap for free


compared to a luden echo 500mana*1.4gold = 700gold value
and a luden gives 32less AP



you do a 7min long push game finish
(2400mana*1.333refund-1000base mana)/7min*60sec * 5per = 26.2mana regen per 5
assume that's 150%mana regen, with a goldvalue of 750gold
add some plants, or back in 5min, to make it 1k goldvalue of regen mana, make it 2k value of regen mana ones you complete ocean drake
to your mana is about 33% to 66% effective in goldvalue to sustain mana, depending on the situation


so,

20cdr*26.667gold*1.666value=888gold
1400mana*1.4*0.333value=653gold
21.75gold per AP* (2400mana*0.03+50)*0.7666value = 2034gold
814gold from AP when build deathcap
mana passive 2400mana*0.333refund*1.4gold *0.333value = 373gold

4762effective gold value



Building it on my Heimerdonker last game,
relic shield adc role/cdr shoes/kindle gem/Lost Chapter/deamans/archangel/warmog/deathcap (6e item could bye Ryla or whatever)

patchy 8.4 no good mana regen + ap items wat 2 do now

Archangel is ridiculously good

2200mana
33.3%more mana heals
20cdr
171AP ones completed deathcap without other mana items
630life shield


2 items 600AP
my heimerdonk Revenous Hunter tree with gathering storm


new archangel is like 2 items in 1
new deathcap is like10%better as the old
free gunblade effects from ravenous Hunter on heimerdonk 6.66time more powerfull then on other champs, so nn AD item, and nn itemslot
and ofc gathering storm and summon eary working on heimer turret
nn more AP ontop of this, deadmans is best to deliver the AP, and a warmog add great to that

Ludens