Was never completely sure how many attacks this combo gives you if you are the one being attacked from a distance. Does the unit's speed ( your unit and your foe) affect how many counter-attacks you will make?
No, it just depends on what percentage health you're at for a follow-up to occur for you. The follow-up from Quick Riposte activates regardless of speed stat as long as you're attacked and meet the above HP requirements unless the foe you're facing has a breaker skill that matches the color and weapon of your ally.
QR *only* changes the number of attacks if you have a unit that would not naturally double in retaliation. Specifically, these are the relevant scenarios.
If your unit would double the attacker and has QR:
Enemy attacks, you counter once, then counter again (no change)
If your unit would not double the attacker and has QR but the attacker would not double you:
Enemy attacks, you counter once, then counter again (QR adds second attack)
If your unit would not double the attacker and has QR and the attacker would double you:
Enemy attacks, you counter once, enemy attacks again, then you counter again (QR adds second attack after second enemy attack)
This is why QR is run almost entirely on tanks and other slow units.
One more thing to note is how QR interacts with other skills.
-Breaker skills targeting the weapon type your QR user has will prevent QR from taking effect (QR Zephiel cannot get a second counter on Swordbreaker units).
-Wary Fighter will stop the second counter from QR, but if your QR user outspeeds the Wary Fighter user, you will be able to counterattack twice.
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