Archon Warp is an ability of a Protoss High Templar and a Protoss Dark Templar. It requires 2 of any Templar, preferably High Templar that are low on energy, or Dark Templar when your opponent has detection, but either will do. The two selected Templar combine into an Archon. The process of transforming takes 12 seconds. The transforming Archon can be targeted and destroyed while in this process. Any damage sustained while the Archon is warping will remain once it has finished warping.
Any 2 High Templar, Dark Templar, or both, can combine to create a powerful psionic entity called the Archon. Archons excel at supporting forces with their psionic shockwaves and splash damage. They can only be produced by combining the expensive Templar, so they are usually created when High Templar run out of energy. Dark Templar can also be used, but they are best suited for other purposes. Another interesting aspect of the Archon is that its total hitpoints are mostly shield points, meaning that if it is near death, it can be drawn away for its shields to regenerate quickly, due to the new shield mechanic implemented in StarCraft II. However, This also makes them vulnerable to the Ghost's EMP, which takes away 100 shield points when it hits. They are most effective against Zerg, as their bonus (vs. biological) and splash damage make them extremely effective against almost all kinds of zerg forces.
When completed, Archons become battle ready. They do 25(+10 against biological), with splash damage. As in the first Starcraft, they are one of the best counters to mass air units, such as Mutalisks along with Psi Storm.