From the Puck spotlight, it seems that there are a few differences. Puck's linear shot seems to not be affected by when or if it hits a target. Couldn't really say with the Aoe burst, since I don't know if that's supposed to be a silence or what. Lissandra's protection plus damage, appears to apply the damage when the spell activates, and can be cast directly on the opponent. Puck seems to only be able to cast it on himself and the damage appears to be applied when he blinks back into the frey. I suppose his linear skillshot is quite similar to her claw though. Visually they're completely different.
This is just me guessing, based on the previews mind you.
Badge Case [Time Badge] StrifeHart is my OTP. services performed at BSC: 2 Riley's Boyfriend on the Pokemon BW2 & X boards. W2 FC: 3783 7001 3142
Well, I know when I went onto the PBE when she first came out when you used her Q or E it was almost impossible to see anything but I played a normal with her anyways and single-handedly carried my team with a score of 14/3/7 and had TONS of fun playing her especially since her E makes it impossible to get ganked or be caught out. I'm definitely day 1 buying her unless I can manage to get someone to buy her for me...... so if anyone wants to buy her for me please do, I would love it! ^ ^