Name:Prepare
ManaCost:1 W
AlternateMode: Split
Types:Instant
A:SP$ Untap | Cost$ 1 W | ValidTgts$ Creature | TgtPrompt$ Select target creature | SubAbility$ DBPump | SpellDescription$ Untap target creature. It gets +2/+2 and gains lifelink until end of turn.
SVar:DBPump:DB$ Pump | Cost$ 0 | Defined$ Targeted | NumAtt$ +2 | NumDef$ +2 | KW$ Lifelink
SVar:Picture:http://www.wizards.com/global/images/magic/general/prepare_fight.jpg
Oracle:Untap target creature. It gets +2/+2 and gains lifelink until end of turn.

ALTERNATE

Name:Fight
ManaCost:3 G
Types:Sorcery
K:Aftermath
A:SP$ Pump | Cost$ 3 G | ValidTgts$ Creature.YouCtrl | TgtPrompt$ Choose target creature you control | SubAbility$ DBFight | SpellDescription$ Target creature you control fights target creature an opponent controls.
SVar:DBFight:DB$ Fight | Defined$ ParentTarget | ValidTgts$ Creature.OppCtrl | TgtPrompt$ Choose target creature an opponent controls
Oracle:Aftermath (Cast this spell only from your graveyard. Then exile it.)\nTarget creature you control fights target creature an opponent controls.