So, problem most people have with Sunfire Cape item Sunfire Cape is the cost and damage output. I personally disagree, so this blog post will just be a bunch of stats showing off how much your tanks are actually doing compared to Sunfire and the cost-effectiveness of the item.

Damage Output

We know thatSunfire Cape item Sunfire Cape deals 35 Magic Damage per second to all surrounding enemies. So, let's just take a look at the damage output from AOE skills from characters with the "Tank" tag.

AoE Skill Damage, Max Rank Cooldown
AlistarSquare Alistar's Trample Trample 27 (+0.1 AP) per second for 3 seconds --
Requires 80 AP to be on par with Sunfire Cape item Sunfire Cape
Skills can be chained to maximise the duration.
AlistarSquare Alistar's Pulverize Pulverize 240 (+0.5 AP) 13 seconds
18 (+0.04 AP) (+6) (+0.02 AP) Magic Damage per second.
Requires 30% CDR or 183 AP to be on par with Sunfire Cape item Sunfire Cape.
AmumuSquare Amumu's Tantrum Tantrum 175 (+0.5 AP) 6 seconds
29 (+0.08 AP) Magic Damage per second.
On par with Sunfire Cape item Sunfire Cape with 2 autoattacks / 17% CDR / 70 AP.
AmumuSquare Amumu's Despair Despair 24 (+2.7 (+0.005 AP))% of target MHP per second 1 second
Always outdamages Sunfire Cape item Sunfire Cape.
GalioSquare Galio's Resolute Smite Resolute Smite 300 (+0.7 AP) 7 seconds
42 (+0.1 AP) Magic Damage per second.
Always outdamages Sunfire Cape item Sunfire Cape.
LeonaSquare Leona's Eclipse Eclipse 260 (+0.4 AP) (+140) 14 seconds
19 (+0.03 AP) (+10) Magic Damage per second.
Requires 18% CDR or 200 AP to be on par with Sunfire Cape item Sunfire Cape.
MaokaiSquare Maokai's Sapling Toss Sapling Toss (180) (+0.4 AP) +280 (+0.6 AP) 12 seconds
(15) (+0.03 AP) +23 (+0.05 AP) Magic Damage per second.
Always outdamages Sunfire Cape item Sunfire Cape if you land the impact damage.
MaokaiSquare Maokai's Vengeful Maelstrom Vengeful Maelstrom 200 (+0.5 AP) (up to +300) 20 seconds
10 (+0.03 AP) (up to +15) Magic Damage per second.
Will only realistically outdamage Sunfire Cape item Sunfire Cape with 40% CDR and 440 AP due to the tradeoff of sacrificing your cooldown for more bonus damage.
TaricSquare Taric's Shatter Shatter 240 (+0.6 AP) 10 seconds
24 (+0.06 AP) Magic Damage per second.
Requires 32% CDR or 184 AP to be on par with Sunfire Cape item Sunfire Cape.
VolibearSquare Volibear's Majestic Roar Majestic Roar 200 (+0.6 AP) 11 seconds
18 (+0.05 AP) Magic Damage per second.
Requires 40% CDR and 32 AP, or 308 AP to be on par with Sunfire Cape item Sunfire Cape.

If 35 Magic Damage per second is too little for you, pretty much AmumuSquare Amumu and GalioSquare Galio are the only tanks who can outdamage a Sunfire Cape item Sunfire Cape without significant AP and CDR investment. And most tanks can't afford that luxury unless they get really fed.

A Sunfire Cape item Sunfire Cape pretty much doubles a tank's AOE damage output.

Note: AOE Abilities with very long cooldowns were omitted from this analysis as I foresaw a very low DPS from them.

Cost

HP Armor Total Difference
Sunfire Cape item Sunfire Cape 450 45 2610 G (Cost)
Value* 1150 G 700 G 1850 G 760 G

You are paying 760 Gold for an aura of 35 MDPS.

35 AD is worth 1297 Gold*. (On the assumption you have near-1.000 Attack Speed). Considering that the AD can only be used on autoattacks (1 target) for most tanks, this damaging aura is an insanely cost effective method of improving your damage output (gives at least 1800 gold worth of stats when there are two nearby enemies).

Conclusion

Buying a Sunfire Cape item Sunfire Cape remains a very good option if you're the tank, want cheap damage, and the enemy isn't completely lopsided towards magic damage.

P.S. It's also amusing every time you see your cape accidentally steal kills from your allies.


* Value of Health is calculated by the formula: 475 + 2.5 (per point of Health over 180)
* Value of Armor is calculated by the formula: 180 + 19.3 (per point of Armor over 18)
* Value of AD is calculated by the formula: 415 + 35.3 (per point of AD over 10)