As we mentioned in the Vigor locations guide, every Vigor (magical power) in BioShock Infinite is associated to a trophy called Combination Shock. To acquire this trophy, you'll have to use the various vigors together in unison.
Much like how oil and fire go well together, so too do some of the Vigors in BioShock Infinite. Used together, these Vigors have a deadly combination that'll serve to make short work of your enemies, especially in the game's Hard mode, and they're an absolute must in 1999 Mode.
You can perform these combos at any time, on any type of enemy, although their efficacy depends on whether or not the enemy you're attacking is immune or weak to certain types of attacks. It wouldn't do much good to use the Murder of Crows attack against a Crow, nor would the Devil's Kiss work against a Fireman.
Also keep in mind that Vigors can be further improved through upgrades as well as Gear.
Here are all the possible Vigor combinations:
1) Possession + Devil's Kiss
2) Possession + Shock Jockey
3) Murder of Crows + Devil's Kiss
4) Murder of Crows + Shock Jockey
5) Bucking Bronco + Devil's Kiss
6) Bucking Bronco + Charge
7) Undertow + Shock Jockey
8) Devil's Kiss + Charge
