There is more to Paradigm shifts than just reacting to an enemy or situation and picking something that suits your style. You can use shifting to position your characters better. For example, if you shift your Sentinel to a Commando, they will run up to the enemies and attack. When you shift them back, your Sentinel will now be far away from the characters that you want to protect, such as Mages. You can also use rapid switches and quick one-bar attacks with Lightning and Snow to have them retreat quickly. Just pick the attacks that makes them jump back a bit.
If you let your ATB meter fill up completely to the max. Perform your action and then do a Paradigm shift as your final action completes. You will instantly get full ATB when you shift so that you can do more actions! After that, just wait for it to fill up again and repeat! This can speed up your battles a lot.
Don't forget about role bonuses! If your whole party has the same role, your stat bonuses will increase! This means that, if you are about to get attacked, you can switch all your characters to Sentinel and take significantly less damage and save yourself some healing. If you are using an attack with a long animation, like Army of One, shift the Paradigm of your other characters to Commando before the damage numbers pop up to stack the bonuses for extra damage!
Lightning-type spells are great to use in keeping your juggles going because they don't have a very long start up time. You can select the spell and expect it to cast almost right away. You can also use it to interrupt enemy attacks and to finish up fights quickly, like when against a Doom counter.
In a real emergency, summon Eidolon. It will restore all your party members back to full health, even those that have been knocked out! Additionally, it will get rid of any status ailments that your party may have.
The Axis Blade, and its upgrades, is a great weapon for Lightning. Whenever Lightning performs a successful hit, her ATB will charge up. Even though it has low stats, the trade off for the ability to quickly build up your ATB is well worth it. If you attack using an Enkindler, you will charge up one bar. Be sure to make the most of it by attack as many enemies as possible with a single attack, since the Axis Blade will charge up for every single hit per enemy. Hitting three enemies with a single attack will charge up the same amount as hitting one enemy three times.
Since we are talking about Lightning, she is easily one of the best characters to use as your leader, simply because of how fast she is. Fast as in "I hit you and I'm done" fast. For example, Lightning's Commando finisher is a simple shoot and a backflip while other characters may do multiple hits for similar damage. What this means is that Lightning will start to recharge her ATB sooner and will get to attack again faster! For spells, Snow is perhaps the fastest at casting, with Lightning and Fang being close seconds.
As you can probably tell, Lightning is one of the better characters to use throughout the game, being well rounded. Hope and Fang, having six roles between them, can easily support any leader and fit any playstyle. Give Lightning the Axis Blade, as mentioned above. If you don't like it, try the Lionheart instead. Hope should carry the Hawkeye while Fang should have the Taming Spear. Use Kaiser Knuckles, Sprint Shoes, Magistral Crest and Super Ribbons as your accessories.
If you are looking for valuables, be sure to grab the Collector and Connoisseur Catalogs! These two items will increase your chances of getting goodies after a battle. Both can be found in Chapter 11. One is at the top of Taejin's tower, just look at the statue after you beat the boss and take the elevator. The other is the reward for Mission 8.
Don't sell anything, unless you have duplicates! Items that seem useless may be used for upgrading your weapons later on. Since you can always dismantle, feel free to mess around with upgrades without worry! However, just be careful when transforming accessories. Sometimes a new and different effect is created, which is not always the desired outcome.
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