seems like eveyone forgot combining two-headed with twin universe, for a 4x damage, rather than 3x (with 2 tu's)
phoenix + adrenaline + momentum + two-headed + pu + pu = unupped otk with 6 cards and 1 high-cost element.
if what keolino said about turns, rather than attacks, we can get it even more interesting:
ruby dragon + unstoppable + sky blitz + two-headed + tu + tu = 6-card fg otk.
silurian dragon + two-headed + mitosis + SoR + tu + SoR + sky blitz + chimera = 312 damage.
also, what happens when using 2 two-headed's on 1 creature? will it cause both attacks to deal damage twice?
Spoiler for if double two-headed causes 4 times damage:
elite charger + two-headed + two-headed + two-headed + two-headed + two-headed + two-headed + tu = 7*2^7=896 damage.
for 5
![Gravity :gravity](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/gravity18x18.png)
, 24
![Earth :earth](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/earth18x18.png)
, and 6
![Aether :aether](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/aether18x18.png)
.
in order to get a fg otk this way, you need 5
![Gravity :gravity](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/gravity18x18.png)
and 20
![Earth :earth](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/earth18x18.png)
, with 6 cards.
In terms of damage/card, you could go with ruby dragon + unstoppabe, for up to 1024 damage;
using sky blitz and tu, you can get the costs down to 12
![Fire :fire](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/fire18x18.png)
, 1
![Gravity :gravity](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/gravity18x18.png)
, 16
![Earth :earth](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/earth18x18.png)
, 6
![Aether :aether](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/aether18x18.png)
and 8
![Air :air](https://elementscommunity.org/forum/Smileys/solosmileys/../../../images/Misc/air18x18.png)
. edit: in case you want to use SN.
I somehow think that this will not be the case...