Was just wondering if most folks run a lot of decks, or just a few. I used to run about 14, but my budget can no longer support that, so I folded down to just four and built three new decks. The thought was to take all the great cards and concentrate them into my favorite decks that are also mechanically sound so the decks are then keepers and always relevant. The new decks encompass cards and strategies I've always wanted to use, but never played until now.

What are you doing?

I run about 10 different casual decks, plus a cube. I have yet to have built an EDH...

~SE++

I have 3 Edh's, one powerful, one funny, one pauper, three Modern decks, a vintage, a number of casual decks, and Mono-black standard.

when I played in standard I usually only had 1 or 2 decks that I used. I am poor so I had to recycle things like dual lands rather than buy more

I have 2 EDH and many other casual decks. I play with many different people who are at various level of skills and commitment. If I only have a few decks, then either I'm stuck playing decks that are much more powerful than my opponent's deck when playing against weaker players, either I'm stuck playing decks that are much weaker than my opponent's deck when playing against stronger players, or I only have 1 deck available to me against each opponent's skill level.

I also have a few casual decks that are more geared towards multiplayer.

I only keep at most 1 or 2 standard deck though and since I don't play other formats too much, I usually only build decks for them before the event and destroy it after the event (usually because I borrow cards so I have to give them back).

I keep 0 decks built.
Limited fo lyfe

I usually have 4-5 decks constructed. Those particular decks change though as I use a lot of the same cards in different decks. My decks are usually casual decks, but I've been know to build some Legacy and Modern legal competitive stuff. Once in a blue moon I'll put together a Vintage list.

I had 8 EDH decks at one point. Now I have 3 and a cube. Usually don't have more than one or two constructed decks built at a time because I have trouble finding a deck I enjoy.

Limited is the best, though.

I have 3 functional decks and a EDH deck. If I would play more frequently, I'd probably have more deck. I should also put my Kederekt Parasite+Forced Fruition deck back together.

I currently only have 3 decks constructed, because I keep losing sight of the character's drive and methods, so I can't manage to bring a cohesive list, or rather, I can't pare it down to a proper size.

Of course, I don't play anything other than casually, so I'm only technically limited by my land pool. I usually have around 5-6 decks at any time, but I deconstructed them all when I bought some RtR and Gatecrash fatpacks.

Oh yeah! I'm very familiar with new sets forcing the upheaval of most of my decks. That's partly why I went to only 7 now. Far fewer cards that will affect me in any set, and thus less to trade for. Shoot, the only reason why I made two of the three new ones was to make a R/G beatdown deck to teach my son with, and to make B/G Dark Depths dueling deck that gets Marit Lage out quickly.

I have...well, more than I can easily remember offhand, so lots. The vast majority of them are casual or old, outdated former-Standard decks that I play casually. I don't really take decks apart, and don't normally update them when new sets come out, so over time I've built up a lot.

What can I say? I like variety.

I find too much variety can be frustrating for me if I have too many decks on hand to play with them all in a given get-together.

I don't really understand that--why would you feel a need to play everything every time? I have a few favourites I play a lot, but I still find it fun to change things up from session to session and play decks I haven't played in months.

Simple, I make them to play them, and as my group all have families, we only get together every two to three months, so it could be six months between playing any given deck. Keeping my decks down in number allows me to re-visit each one, potentially multiple times, and I like that.

Let's see. I've got like 8 or so casual decks, but I almost never play with 60-card decks anymore, so I really should just take them apart. I just built a Modern deck to get ready for the Minneapolis GP next May. Might as well get started early lol. My format of choice though is edh. I've got 12 built right now, and I plan on picking up the Bant precon plus I've started tinkering on another new one.

Pro-tip: Those holiday boxes are FANTASTIC at holding decks. I'm definitely picking up another one this year.

I have upwards of thirty decks, but mine are casual format only and don't see a lot of change once they finally get built. They're all built around some aspect of the lore. One for each walker since the Mending (Except Venser for being an awful character and Domri because I hate the little jerk), as well as one for the White Phyrexians, One for the Blue Mirrans, one for each guild, and one for each Shard.
I also have one strange little white spirit tribal deck, but that's complicated to explain.

I have 1 edh & something like 10-13 other decks that conform to Vintage b/r. I've shuffled some things around recently & 3-4 or so of those are new decks, so I don't remember what I actually have together atm.

A bunch.