Arc = more current than no arc?

Does an arc produce more current or voltage than if there was no arc?
e.g., you have two probes. Your hunting for rats. You touch both probes to the rat, but it just shocks em. But, if you raise one of the probes so its not touching its body and you let the voltage arc into its body, will it "hit em" harder?
Ive done this, and it appears that if it arcs, it knocks em out harder.

But I just want scientific evidence behind this.

The current output depends very much on the source resistance of the power supply. If there is enuf current, you could easily kill yourself by touching the probes. Since you are not dead, I suspect the supply is current limited. When the probes touch the rat, the current is close to the limit. When the probe is lifted, the current decreases but the voltage increases to maintain the arc. This will burn a hole in the rat and probably disable him.

If it is a simple system, not arcing will transfer more power to the load (rat).

If it's a resonant transformer, the arc will change the dynamics (inductance/capacitance) of the load, which may increase or decrease the net power to the load.

One "process" that uses an arc is corona discharge treatment. Welding is the most common arc process that comes to mind. Arcs are also of concern to circuit breaker and switchgear manufacturers. You might find the science you need by looking into these areas.

The device Im using is a modded stun gun. It seems that it "stuns" the victim harder if it arcs than if both probes touch the victim.

Hmmm..