Might and Magic sale

Anno and Trials is also on sale.

Trials is a very awesome game, but is dragged down ALOT by a very poor console port and uplay bugs.

Onto you question: Get V. I played it and have had some fun with it. No experience with the others though.

Definitely HoMM V with the expansions.

There is no H3 on Steam, so you should get Heroes V with expansions. Or, if you don't care about campaign, just Tribes of the East.

If you plan on buying Heroes 5 then get the expansions too. They add a lot of gameplay stuff.

Don't buy Heroes 6, if you want a bug-free experience(there's a lot of game breaking bugs).

You can picked up HoMM I-V and Heroes Chronicles from GOG for cheap when they do sales. Think it cost me 5-10$ for all of them.

I think you are mixing the different sagas of the game.
If you want a classic first person rpg, then play Might & Magic from I to X. (I dont like too much this rpg type)

If you want a turn based estrategy game, with some rpg things and city management, then play Heroes of Might & Magic I to VI. (I have all the collection, I recommend Heroes V with the two expansions, and you can buy Heroes III and his expansions in GOG. They´re the best)

If you want a Fantasy FPS, play Dark Messiah of Might and Magic.

If you want a Puzzle game, play Clash of Heroes

And finally, the King´s Bounty saga is like Heroes, but without city management, only one hero, and with more rpg things. (Heroes saga is best in my opinion)

If you want to know the complete story of might and magic, you need to jump from saga to saga.

Since you like RPG and strategy games, I'd say you're talking about "Heroes of Might and Magic" saga. If that's the case, and you like playing older games, then I definitely recomment HoMM III and IV. I've played quite a bit of them back when they were popular and in my opinion, those two are what made the series. V and VI are okay, but they dont have that HoMM feel that parts I-IV have. I actually started playing both, but wasnt interested enough to finish them (especially V).

Took a look at a couple since I want Dark Messiah and Clash of Heroes, but both are more expensive here, so no getting them for $2.50 Steam wallet. Bah, humbug.

Only Legacy is interesting to me (I wouldn't touch the others with a 10 foot pole), but it happens to be the one with the worst deal :-(

Thanks everyone for the help. I've also done a little bit of research and found out that I only need Tribes of the East since there's a fan content pack that adds the campaigns to it.

Gonna try and get Dark Messiah but i think the sale will end before i can get my hands on it.

Clash of Heroes is really fun, I'm really resisitng the urge to buy it...despite that I've already finished it on my handheld system ;)