In my opinion if you try to port League of Legends to CS 1.6 you could learn from SMITE in the way spell casting works. SMITE is a MOBA based on League of Legends except it's 3rd person (camera is locked) behind your character instead of the "top view" in LoL.
Here's a gameplay video if you want to see what I mean.
(note that SMITE is free to play if you want to try it by yourself)
Another point that differs from LoL and SMITE is the auto-attack (right click on an ennemy) :
In both game differents characters have differents auto attack animations, range and speed but unlike in League of Legends where you only need to right click to auto-attack with an ennmy by default, in SMITE you need to aim the direction you want the default attack to go then right click hoping that the ennemy is in range and won't dodge it.
I think this kind of attacking system is more appropriate to a fps game than the one in LoL. Also I believe it's more doable with AMXX and that you could recreate that part of SMITE gameplay with LoL Champions using weapon models and sprites.
I hope my post is clear enough and that you'll consider my idea
If you need any help with champion knowledge or anything about LoL itself feel free to PM me.
Good Luck on your project man.
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