Let's say I were to fuse out a Five-Headed Dragon from my hand with a Polymerization and five Dragons. Would that count as a discard so that I'd be able to refill my hand at end of turn with a Super Rejuvenation?

Hm...yeah, that's what I was afraid of. So I have to find another way to not dig myself a hole when I summon this thing, then.

So far, the "best" way to use Super Rejuvenation is with Spirit Ryu (seems to be what it is made for anyways)...since Polymerization merely "sends to the Graveyard". You must actually "discard".

The "best" way (in quotes because any way you slice it, FHD isn't easy to Summon) to Fusion Summon "Five-Headed Dragon" is by using Monster Tokens that have been changed to Dragon-Type by "DNA Surgery". "Scapegoat" is an obvious choice for this, as well as any other card that allows you to gain monsters without sacrificing too much of your hand.

Actually, I just thought of something that could work well: "The Agent of Creation - Venus". As long as the 3 "Mystical Shine Ball" are in your Deck, you'll be able to have 4 monsters (Dragon-Type via "DNA Surgery") on the field for "Five-Headed Dragon"'s Fusion Summon for the relatively low price of 1500 Life Points (1 per Shine Ball). Since you'd only need 1 more Dragon-Type beyond that, this would probably save your hand size by quite a bit.

so whats the FHD's effect anyway???

Stats: Dragon / Fusion / Effect / Level 12 ATK/5000 DEF/5000
Card #: SD09-ENSS1
Found In: Dinosaur's Rage Special Set
Description: The Fusion Material Monsters for this card are any 5 Dragon-Type monsters. This monster cannot be Special Summoned except by Fusion Summon. This card does not take any Battle Damage and cannot be destroyed by battle with an ERATH, WATER, FIRE, WIND, or DARK monster. (Battle Damage is still inficted to players.)

interesting....gonna need to add that to my dragon deck as an alternative option if i have dragons, when the dont go together.....

0-)

As far as the "best way", what about dragon's mirror. Should be pretty easy.

I have always found Dragon Mirror to be the "best" way of summoning Five God Dragon...I only meant the "best" way in terms of Super Rejuvenation, though.

spirit ryu + super rejuvenation + dragon's mirror would make a nice combo.

What other ways can FHD be summoned, other than Dragon's Mirror?

Should be obvious...

Polymerization
Fusion Gate
Dragon Mirror
Future Fusion

....that's it...nothing else works on it currently...Cyber-Stein, Metamorphosis, Summoner of Illusions, etc can't work, obviously since they're not Fusion Summons...

I thought the only way for summoning that you could tribute Scapegoat tokens was for Toon monsters. If I am wrong please explain.

Scapegoats can't be used for a Tribute Summon. This is correct. However, FGD is not a Tribute Summon. He's just a fusion monster.