Tribes: Ascend/Perks/Sonic Punch
"Your melee attacks now cause a shock-wave that knocks back nearby enemies. With the final upgrade of this perk the shockwave will force flag drops on enemy players."
Sonic Punch applies an impulse to an enemy who is meleed, and the final upgrade will cause the player that is meleed to also drop the flag. Sonic Punch can be used on thin walls to hit a player on the other side. This is a Secondary Perk.
Upgrade 1: Increase knockback
Upgrade 2: Increase knockback
Upgrade 3: Forces flag drop
Infiltrators enjoy this perk the most, and can use it very effectively. With their stealth capability, Infiltrators can sneak up on enemy players, stick them with a grenade, and then boost them away with a melee attack. They can also retrieve the flag from someone hiding in a base, by sneaking up on them and meleeing them. Infiltrators can also knock enemies off of ledges into the bottomless pits.