Saw a thread like this for abilities. Simple really, make up a signature move that's exclusive to one Pokemon family line.

Hard Mode: Make it not grossly OP.

Random Mode: http://wyncorporation.com/pokemon/

>>Legendary birds:

Ice Storm/Thunder Storm/Fire Storm
10 PP/120 BP/100 ACC (Ice, Elec, and Fire respectively, Special)
The user flies around in a frenzy, raining down blasts of (Ice/Thunder/Fire) for 2-3 turns before becoming confused. May (Freeze/Paralyze/Burn the foe(s))

>>Chikorita line
Overgrown Canopy
20 PP/70 BP/100 ACC (Grass/Special)
Thick, flame resistant foliage flies out to attack the target. Super effective against fire type Pokemon and may raise the user's defense.

>>Cyndaquil line
Blazing Burst
20 PP/70 BP/100 ACC (Fire/Special)
User releases a blast of intense, dry heat that may burn the foe. Super effective against water types.

>>Totodile line
Torrential Strike
20 PP/70 BP/100 ACC (Grass/Special)
User attacks with the force of a flash flood, possibly lowering the foe's speed. Super effective against grass types.

>> Random Mode: Electrode
Overload
5 PP/250 BP/100 Acc (Elec, special)
The user gathers all it's energy, releasing it in a large explosion to damage everyone around it. The user faints upon using this move.