**You can only choose chips of the same letter consecutively or choose chips with an asterick (*) which allows for combinations with any other chip letter but only 1 LETTER can be used at any given chip order UNLESS they're in consecutive alphabetical order (So, L*L is valid but L*E is not. However, ABC and CDE are valid as well)
It's an ABS with a default attack which can be charged up. It's a direct forward (well, right technically) shooting attack and later on in the game, your main character can be customized to shoot elemental shots or other properties (paralyze them, burn them for a while, etc.)
Different terrains yield different effects (slide across, metal can't have holes in it, cracked meaning you step on it and a hole appears, holes which prevent you from moving on and ground based attacks cannot bypass. Only some of the available options)
Chips yield different effects. They can shoot attacks in different patterns (spreaders, shotguns, V shots), deal different elemental damages, they can be melee weapons with limited range (i.e. 2 squares to the right or the 3 squares that make up a column). Certain chips are special in that they allow for more. Like, 1 chip allows, depending on key input, a different type of sword when used. Another summons an ally to deal certain effects before leaving, others recover you, etc.
Finally, certain chip combinations allow for "super attacks" during which you're invulnerable and allow for infinite uses of the chip for a certain duration when activated.
That's how you could've described it