Blazblue (like every other fighting game that isn’t made by Capcom) uses the standard international notation for combos. Directions are referenced by numbers. Imagine a computer’s number pad:
789
456
123
1 is down-back, 6 is forwards, 5 is neutral, etc. Litchi has lots of half-circles, so instead of writing 41236D~X all the time, you’ll see ittsuX. It’s intended to make the combo easier to read that it would be with numbers.
It does help to realize you should be hitting the jumping C as late as you possibly can after the B; that gives you the most time to land and dash, though if you wait too long the C won’t come out and he’ll tech. Fortunately the timing doesn’t seem to get much tighter for the second repetition, so once you get the rhythm down you should get it pretty fast. Still a pain in the ass considering how many easy ways Litchi has to get that sort of damage =p
Depends, with staff or without?
Without staff your kinda screwed. You can either wait for on opening for a 2A, IB to make an opening for a punish, barrier to push them away creating an opening when they run back in, or counter assault.
With staff you have a dp, better moves in general, and can still use all the other options. Itsuu is also and option, but not a very good one.
Litchi’s 236a also helps. The ground version has a period of invincibility to air attacks, so it will stuff a lot of things. Very useful if they use a lot of jumpins in their pressure. However, it’s unsafe on block, so be wary of empty jumpins.
Litchi’s 2a can be a nice anti air as well actually, because her hurtbox is so small during it, most characters have to do their jumpins a lot deeper to deal with it, which makes them more vulnerable to other attacks.
With staff, 4d can be useful, because it is invulnerable to lows on frame 1. Depending on who you are defending against, that can be useful for getting out.