They seem to be determined not to let me pass. They attack with unlimited focus.
The Temple Guard slowly wanders around, occasionally pausing to fire two targeted missiles. Like most in the game, they target the players location at the time of launch, so are typically easy to dodge. If they are not dodged, however, they can deal significant damage because it is likely both missiles will connect. This mob will also sometimes stop and buff itself with a shield similar to that of Providence, making it much harder to take down.
Elite Temple Guards can come in any of the five variants, Blazing, Frenzied, Volatile, Overloading, and Leeching. The Overloading variant can be surprising because the typical Tesla Coil effect also applies to its missiles, causing a shock during travel and detonation that is much larger than the missile or its blast radius.