Evil twin changes

Removes the focus required for evil twin but limits the casting to one
summon per room.

The twin now hits harder and faster but dies very quickly.

The idea here is to take a useless spell and give it a tweak so maybe it
can be used in combat and a distraction that does some damage. The
target can quickly switch to and kill the twin if they want to or tank
the damage for awhile but it does add up over time.

Procs from weapons can be crazy because of the twins attack speed but I
believe this just forces the target to disarm themself or switch weapons
until the twin is dealt with.