Karax by Demolij

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Karax is a global mage with amazing poke but limited sustainability. His long-ranged attacks are delayed and don't deal a ton of damage on their own but combo well with his other skills. An important factor is that he really needs vision to take advantage of his kit, so he's weak to stealth heroes or long-ranged skillshots he can't see. His Trait allows him to cast a large amount of abilities rapidly, but if he keeps using his abilities you have to wait a while to keep casting, and Solarite doesn't regenerate in the Altar of Storms. This encourages you to pace yourself rather than simply unloading on the first enemy you see. The other aspect of your Trait empowers your damage and encourages you to actually get up close to your enemies, because your base health is higher than other mages you can afford to actually attack them and empower your consecutive attacks. Because of both parts of your Trait, you're not going to want to sit in base casting spells rather than actually helping your team. Karax works great as a poke-y supplement to global teams, or as a counter to enemy poke.

Orbital Strike is your bread and butter damage spell. It requires an enemy target to fire and does give them a split second to get out of the small AoE, but really they're pretty much always going to get hit by it unless they have a dash. At full Solarite it can be used about 9 times in a row, but then you have to wait 8 seconds for each cast. Basically it's a strong damage tool and can be great for bursting an enemy down from across the map, but you have to pace yourself or you'll be left with no Solarite and no damage. Remember that the ability can barely kill an Abathur by itself and needs to be used in conjunction with your teammates. There's also a limiter in place where it can't be used to interrupt channels indefinitely by itself so you have to rely on your other skills. This skill is especially useful if you plan on solo-laning, because it has a small amount of AoE and can be nice for clearing waves, while still being able to hit enemies far away.

Khaydarin Blast is a combo ability and a big part of your burst damage. The skillshot it fires moves rather quickly but is blocked by buildings. If you do land it on your target though, the damage it deals is pretty sizeable and can let your allies kill them much faster as well! It gives vision for your Q letting you hit enemies from far away without needing teammates, although at that range it may be hard to hit. Chrono Boost might seem like your weakest ability, but a global utility boost for a group of allies with a long duration is not to be sneezed at. It's not as useful on you as it is on your allies, but if you do want to have it on yourself it's ideal to apply it on all of you at once. Keep your eyes on allies all over the map to see who needs it the most, given how cheap the ability is.

Solar Lance deals raw burst damage in a huge AoE (the sweep is quite thick) and is your only real method of hitting buildings. The beam moves somewhat quickly, completing the full length in about 1.25s, and the ignited ground will deal the total damage of the beam if the enemy stands in it, but the ability is limited by the weighty Solarite cost that essentially halves or fully depletes your pool if cast twice. Meanwhile the Colossus has a very short duration with a hefty Solarite cost, and has significantly shorter range than the rest of his abilities while becoming useless if Karax dies. Fortunately this is made up for the fact that it's basically a map objective on its own, dealing sizeable AoE damage while having a gratuitous health bar, letting it function as a spearhead for a push or similar. Of course, the cost means that you can't cast any abilities for a while once it's summoned, so it's a very all-or-nothing ordeal.

Talents support a variety of playstyles, with many early talents letting you spec into more damage when you synergize with basic attacks, or letting you deal more damage without needing to get close at all, and letting you spec into more burst or better sustain. There are a few key talents I'd like to draw attention to. One is Purifier Blast, which empowers Khaydarin Blast against distant enemies for high-damage, long-range snipes. Another is Reclaimation, which is stellar for pushing in on enemy fortifications or as an easy way to finish off an enemy that thinks they're safe. At level 16 is your biggest playstyle changer, with Phase Detonation giving more raw damage, Solarite Efficiency giving more utility, and Temporal Field reducing your damage for a very strong AoE slow (which synergizes with Purifier Blast for easier hits). Finally, at level 20 there are 3 talent choices that apply a similar effect to both heroic option to suit the circumstance. Annihilation Cluster lets you cast them without being at full Solarite to supplement them with basic abilities. Thermal Lance gives you better poke and lets you wipe waves easily. Solar Flare purely supplements your hero damage with some %health damage, but needs to be constantly reapplied for best effect.

Statistics
HEALTH: 2000 +4.5% per level
REGEN: 4.21 +4.5% per level
DAMAGE: 52 +4% per level
ATTACK SPEED: 1.83 per second
RANGE: 5.5