i was support role and sold frostfang for deathcap lategame

7198 Dark Harvest and cheap shot damage, from 65842total damage, thats 12.27%more damage from thease 2 runes
Normaly you get a little less then you get from arcane comet, but this game i got decent

then also, have 5/5 Ultimate hunter ontop of 1 cloud drake
85/60===>41.666%more shroom spam with 1 cloud from 1 rune
100/75===>33.3%more shroom spam with 0 cloud from 1 rune
60/35===>71.43%more shroom spam with 4 cloud from 1 rune

60/55===>9.09%more shroom from cosmic insight at full build
75/70===>7.14%more shroom with 20%cdr items and lvl9 from cosmic insight

then you have, ghost poro vision and AP, and 300gold from boots and 10ms, instead of gathering storm
and you have redemption gold dump, from forbidden idol, to replace manaflow band and transendance

if have 2Clouds or more, better rush the redemption before the voidstaff/deathcap, to spam them infinite mana shrooms!

------------------------------------
Maybe i only seen 1Teemo player shroom equal as good as my 3.3M Teemo!
1) support role is better shrooms
2) max w first is better shrooms
3) not shroom minion waves (maybe 1in 5waves can be shroomed as adc Teemo or top Teemo) when do so, use battleshroom to hit opponent
4) only put shroom togethor or bounce shroom after lvl16
5) never overcap your shroom storage
6) keep running, to spread shrooms
7) patting
8) shrooms for allies
9) shroom where the action will be in the nxt 4min