Starcraft II - Q&A Batch 36

Well, they can't ascend cliffs or cross bodies of water, if that's the answer you're looking for Jiff

 

@ Neon, You can't think of Hallucination as free units as it costs energy that would otherwise go to casting Psi Storms. If Psi Storm still costs what it did in SC1, then every two casts of Hallucination is one Psi Storm +5 extra energy, 80(40+40) VS 75. With Psi Storms being such a significant portion of actual Protoss damage output, you must weigh Hallucination's effectiveness VS Psi Storm.

Using the Zealots VS Banelings example again, 2 or so Banelings could probably kill 4 or more Hallucinated Zealots. With Baneling splash now doing 100% over its entire effective radius, it would be especially easy. Now if you compared that to a single cast of Psi Storm, which cost 5 less energy, you could easily kill more than that number of Banelings. Even where the enemy player moves targeted units away to prevent full damage, you can easily deal damage equal to 2 Banelings' worth of HP(120), if not a whole lot more.

However, the difference is, Psi Storm is an ability used actively, it is direct damage output. Even with excellent micro, it is virtually impossible to completely avoid Psi Storm damage. Psi Storms also give you a tactical advantage in which, your enemy must now move their troops dependent on your actions or suffer great damage and casualties. Hallucination is not the same, your enemy would still be safe to keep to their plan of attack and troop movement. Hallucination only wastes a few attacks from the enemy here and there. Banelings on attack-move or just Siege Tanks going about their usual business would flush your spell energy investment down just drain very quickly.

So Hallucination doesn't really "do its job" just because some Banelings were thrown at 'em to take 'em out. Because Psi Storm would've otherwise taken out more Banelings, or equal or greater worth in HP. And that's just Banelings, Siege Tanks easily killing Hallucinated copies left and right would have an even easier time.

I pointed out that the only major difference between SC1 Hallucination and SC2 Hallucination being energy cost for a reason. If Hallucination was worth the trouble, it would've been used more. Sure, its high energy cost does take away from general usability. However, the spell is essentially the same. People come up with and pull off all kinds of obscure strats. But the fact is, Hallucination is virtually unused outside of the spam Shuttle/Arbiter strat once in a blue moon. I strongly believe that having the spell copy every unit's behavioral trait is by far the most important factor in the spell's actual in-game usefulness.