Level Up, RedoneEdit
First to demonstrate Alternate Rise's white cards is Adept of the Sword:
The idea for this came directly from Rise's card, Student Of Warfare, and I used its level abilities directly since I thought they meshed so well with the idea of a warrior becoming better at fighting.
The more interesting part in this card, however, is its level up ability: "Put a +0/+1 level counter on this". Why the change from "level counter" to "+0/+1 level counter"? There are several reasons. First, in the original Rise levelers didn't get better for sometimes as much as six mana being spent on level up abilities, because they hadn't gotten to the next level. And you can get a lot for a six-mana card, usually one that would win you the game in just a few turns. It didn't seem fair that so much mana could potentially go to waste, so it only made logical sense that the additional leveling up made the creature better in some way. Of course, altering a creature's power or toughness was the first idea that came to mind. If it had been +1/+0 counters, however, the potential for abuse would be too great. After all, usually creatures get about +1/+1 per additional mana you spent on the initial casting (read: higher mana costs.) If you could get +1/+0 added to a card several times each turn, you could easily wind up with a card with ten or even more power, and the idea in Alternate Rise, as in Rise, was to keep the Eldrazi at the top. Meanwhile, having a creature's toughness pumped up to ten wouldn't do you much good except to make it a really good blocker, and hence this method would be far less prone to being abused.
The next major reason is that spending two mana per level winds up costing you a lot of mana by level six (the highest level they get to), and the last thing a player would want to see is to see all that mana getting nullified by a Shock or Lightning Bolt. So while inexperienced creatures are weak and aren't worth much, you'll generally have few high-level creatures so they'll be both strong and rare, and hence particularly valuable. Thematically this makes sense too: you'd expect a warrior to become better at surviving dangers the more battle he's seen or the more skilled he's become, almost regardless of whether that creature is a fighter or a wizard, while you would be incredulous if all leveler creatures became capable of dealing more damage with each level, especially if it were, say, a blue wizard.
The third reason is that in canon Rise, players tend to focus exclusively on pumping a creature to the next level plateau, then on to another, with the end result that the creatures tend to gain a lot of levels in one go, and gain levels only twice (once for the first tier ability, and again for the second tier ability). By making it so that your creatures become better at surviving battle in general, Alternate Rise's level up mechanic encourages players to shore up weaknesses in their array of creatures as well as giving players something useful to spend their excess mana on if they've already reached the top tiers for their levelers. Hence it becomes reasonable to level up your more powerful creatures' toughness to, say, ten, which is way beyond the second level tier, if that would mean it would have a better chance of withstanding an assault.
You may have also noticed that Adept of the Sword's mana cost of is quite high for what is initially a 1/1 creature. This is made up for the fact that its level up curve is considerably more favorable than those of canon Rise. Essentially, in order to make the casting of Adept of the Sword a good deal, a player would have to level it up at least a few times with his or her excess mana, and at least get the first level tier's ability. And because leveling up is so much better in Alternate Rise, players wouldn't feel hurt spending the additional mana. In the case of Adept of the Sword, it has a good level ability at levels two through five, then loses it and gains a much better ability at level six and above. That 4/1 is actually quite deceptive: by the time the Adept of the Sword can use his second level ability, he's already got six +0/+1 counters and so is actually a 4/7. And that's just the start - if you spend another on him - which you can easily wind up doing if you don't have a card you want to cast in your hand - he's now a 4/11!
On to the flavor. The Kor remain a white-color race but are also adept at combat. Many have not only taken up arms against the enemy, but have also practiced and learned the ways of war from a master in the art, so that they are able to use the sword whilst performing the various acrobatics the Kor traditionally do with their hooks and ropes.
Other White LevelersEdit
Here's another pretty standard leveler:
With many of the soldiers of the human nations injured or killed in the intense battles against the Eldrazi, many of those who would normally not see combat have been pulled into the fight. Battlecalled Squire exemplifies one such kind of soldier: He's originally staying and guarding his knight when he's at level 0, as a plain 0/2 with Defender. Once he's blocked an invader, though, he decides to keep his sword and becomes willing to charge on the offensive. After level 0 he loses Defender and as he gains experience in fighting he gradually becomes better at defending himself as well as defending others. So to recap: At level zero, he's a 0/2 with Defender; at level one, he's a 1/3 (don't forget the +0/+1 counter); at level three, he's a 2/5 with Vigilance. Talk about a fast-paced growth in battle prowess. And what's more, you don't even have to spend mana to make him better! With Vigilance, he could potentially level up twice in one turn. Furthermore, opposing players would even think twice about attacking you if you control one of these, lest he or she end up getting attacked by a 1/3 soon to become a 2/5. While he's nothing that would hold back an Eldrazi, he's definitely a pretty cool soldier.
White's been under an awful lot of siege ever since the Eldrazi awakened. Here's another instance of a white warrior that's been hard-pressed:
The Fleeing Outrider is a novice horseback rider - perhaps he stole someone's horse when news of the approaching Eldrazi came around - and who's desperately trying to escape the destructive reach of the Eldrazi, but he's barely able to avoid them, since they seem to be roaming everywhere. As such he winds up engaging with either Eldrazi (and his allies die while he manages to slip away), or with other forces intent on stopping his progress. Either way, he becomes better skilled with horseback fighting, learning first how to gain an advantage on the enemy and then how to slip past them altogether with his faster speed. By level five, he's a 4/7 that can most likely strike every turn to deal significant damage to your enemy, whether or not they have an Eldrazi in play!