TCG Rulings

• Sending “Hedge Guard” to the Graveyard is a cost. This effect does not target.^[1]

OCG Rulings

• The effect does not target.^[2]

• Sending this card from the hand to the Graveyard is a cost to activate the effect.^[2]

• The effect of "Hedge Guard" only affects the monster that is battling when the effect resolves. It does not apply to other monsters you control.^[3]

References

1. ↑ Konami Gameplay FAQ: Raging Battle -- Card Rulings (version 1.2)
2. ↑ ^{2.0 2.1} Konami FAQ: Effect Monster > Hedge Guard
3. ↑ Konami FAQ: Does only the battling monster have its ATK halved by the effect of "Hedge Guard"?