The limits of Jaswinder's powers are, as I understand it:
- 1000 kilograms worth of energy, though not antimatter (spoilsport!)
- effects within 1 km radius (though the effect could be a point or a 1km sphere)
- the effect is not logical
The key is how one interprets "not logical;" here are three possibilities:
"Doesn't follow the logical rules of the universe"
Picture, if you will, a circular target with three rings. The center of the target is a stable object. It will probably be a lump, or dust, or something else with no recognizable shape, but at least it will exist. The second, much larger ring is radioactive matter; if Jaswinder makes anything with some sort of mass, it's probably going to be radioactive, because none of the atoms will have the right number of protons, neutrons, or electrons to be stable. The outside ring is energy; whatever Jaswinder's magic produces, it either decays quickly, or was simply energy to begin with. Finally, if the target is missed completely, the thing that is created can't exist in our universe, to the point of not actually interacting with the universe.
When Jaswinder uses his powers, it is equivalent to standing at the opposite end of the universe and throwing a dart at random. While it's possible that he creates something, or makes a burst of raw energy, the overwhelming chances are that whatever he creates will never interact with the universe at all. In other words, if Jaswinder used his ability all day, every day, by the end of his life, he will probably not have more than a single observable effect to his name.
This one is much more exciting, as it actually makes Jaswinder into a bomb, though not a reusable one. Given any configuration of sub-atomic matter or energy, most of the time the "matter" Jaswinder creates will be nothing more than stray electrons, protons, neutrons, or raw energy. The energy and matter would be scattered around Jaswinder in a 1 km sphere. The random matter would mostly be free sub-atomic particles, which will wreak havoc on matter.
The fact that Jaswinder survives the explosion would be great, except there's a pretty good chance that the ground Jaswinder was standing on would be vaporized or otherwise destroyed, leaving him to plummet into a hole that will be as deep as 1 km.
If Jaswinder wants to survive, he would have to calculate how much energy he should draw to be able to fry the area around him without damaging the ground he is standing on. Of course, he doesn't know if the energy will be evenly spread around the 1 km sphere, or piled in a tiny point just under his feet.
"Random, but recognizable"
Unlike the previous two answers, here Jaswinder's power creates something that not only can exist, but is recognizable. When he uses his powers, he creates an object somewhere in a 1 km sphere that weighs between 0 and 1000 kg. The object could be anything: a bubble of hydrogen, a 1000 kg gold statue of his grandmother, 100 dead mice, an exact living duplicate of Elvis, or a two-story-tall supercomputer; what it is shaped like, what it is made of, and whether it is organic, inorganic, living, dead, or somewhere in between is completely at random. Oh, and it appears anywhere within 1 kg of our "hero".
At first, that ability would be really cool; he would summon a gold statue nearby, and a wind-up robot that can talk. Of course, it wouldn't be long before he also calls up a perfect copy of his grandmother 1 km above his head, a cute puppy embedded in his bedroom door, 500 kg of raw sewage into his house, and 100 kg of spiders in his own bed.
Jaswinder would not want to use his power. Random is bad.