Guild Wars 2

Apologies if this has been asked before, but is the damage/crit chance of an attack calculated upon initiating the attack or upon landing the attack?

Suppose I’m a teef with 40% crit chance, and suppose my steal grants me fury. If I initiate an attack, steal to a target, and then land the attack, does it have a 40% chance of crit or a 60% chance of crit? Similarly if you initiate an attack and a party member grants you might before you land your attack.

You get the boons as soon as they appear on your boon bar. It depends on minute timing to know what, if and when it applies to what.