From Unofficial Homecoming Wiki
A character is "knocked back" when they are thrown back and to the floor by the force of an attack.
- If a character has knockback resistance or protection, the knockback will be decreased or ignored based on the outcome of the formula.
- For a character to be knocked back, the final magnitude must be above a certain threshold; under that threshold will be turned into knockdown. The threshold is between 0.7437 and 0.8174, and is most likely 0.75.
- Some enemies are resistant to knockback, and any knockback used against them will be turned into knockdown.
- Additionally, if the target is sufficiently high enough level, the Purple Patch will turn knockback into knockdown.
- Increasing knockback increases both the magnitude of KB and the resultant distance thrown.
- If a character is standing on the ground, they will be thrown back and must get up off the ground at the end of the KB. They cannot move or fire powers during the animation.
- If a character is flying, by any flight power (Hover, Rocket Pack, Group Fly, etc), they will flip in the air. The time necessary to wait through the animation for Flying knockback versus Grounded knockback is approximately half.
- NOTE: Hover used to provide complete knockback mitigation: you were capable of firing powers and moving around while the flip animation was going. This was a bug and was fixed in August 2008.
- Knockback always occurs directly away from the source of the knockback-causing power. This produces unintuitive results in the case of enemy-targeted AoE powers like M30 Grenade, since the natural expectation is for enemies to be knocked away from the central target rather than away from the shooter. Ground-targeted AoEs such as Bonfire produce knockback away from their centers because those powers' effects are produced indirectly, through a pseudopet at the center of the affected area.
- Explosive Blast from Energy Blast.
- Power Thrust from Energy Manipulation.
- Force Bolt from Force Field.
- Most, but not all, Armor sets provide knockback protection and resistance.
- Acrobatics provides protection, but not resistance.
- There are Inspirations that provide protection, but not resistance.
- Increase Density provides protection, but not resistance.
- There are Invention Enhancements that provide protection, but not resistance.
- An Empowerment buff provides protection, but not resistance.
- The Overwhelming Force Enhancement Set available as a reward for completion of the Summer Blockbuster Event can convert Knockback into Knockdown.