I've been working on a way to make Unown more interesting and useful. It should absolutely remain a mediocre gimmickmon, but accentuating its "mysterious" aspects would go a long way toward making it more likable.
In a new region, Unown usually appear in horde battles. The Unown in these horde battles always spell out a five-character word; there are 151 different possible words wild Unown can spell. Because they are usually encountered this way, certain Unown are much more rare than others, such as Z and Q. Vowels are common.
Various Wild Unown words:
>H-E-L-L-O>P-L-A-Y-?>S-M-I-L-E>F-R-O-W-N>P-A-N-I-C>H-E-L-P-!>F-I-G-H-T>C-A-T-C-H>T-R-A-D-ECertain doors can be unlocked by assembling the correct five-character word of Unown in your party. Yes, they have to be in order. 5 is a significant number in the game's story and lore; assembling Unown that spell B-L-A-C-K or W-H-I-T-E will reveal Zekrom/Reshiram respectively, among other secrets.
Mega Unown is added to the game. In terms of appearance, it's a constantly-moving swarm of Unown with its primary letter at the center. Mega Unown remains a gimmickmon, but its gimmick is marginally more interesting. Its stat spread:
HP 48
Atk 72
Def 48+25 = 73
SpA 72+25 = 87
SpD 48+25 = 73
Spe 48+25 = 73
>Ability - Mysterious Power: Hidden Power's BP is doubled, and it gets one of six added effects based on its type.The type effects are as follows:
>Fire, Dragon, Ghost: Burns the target>Poison, Bug, Grass: Badly Poisons the target>Electric, Ice, Rock: Paralyzes the target>Psychic, Dark, Fairy: Confuses the target>Fighting, Normal, Steel: Hidden Power's BP is tripled instead of doubled (BP 180)>Water, Ground, Flying: Lowers the target's Accuracy>>24803836I like the idea of locking your opponent into one attack, but forcing it to be the first slot is too taxing. Would be more fair if it just choice-locked the opponent when they choose their move, but an ability like that wouldn't be a good fit for weak Unown.