You’re at a fast-fold table. Two players show 25/20 stats. Both look like solid regs. One has 100bb after 1000 hands. One has 160bb after 300 hands. Which one is actually solid?

If you’re just looking at their VPIP and PFR, you can’t tell. They both look competent. They both have reasonable, reg-like stats. But one of them is bleeding chips, and one of them is crushing.

Stack trajectory tells you which is which. And in modern fast-fold poker, this distinction matters more than ever.

The Auto-Fold Problem

GG Poker and other fast-fold platforms have a feature that’s made life both easier and more complicated: auto-fold charts. Players can configure these charts to automatically fold certain hands from certain positions. Set it up once, and the client will auto-muck 72o from UTG without you even seeing the hand.

This sounds convenient. And it is - for the players using them.

But here’s what it’s done to the player pool: it’s allowed shit players to play solid pre-flop ranges without actually understanding pre-flop strategy.

Before auto-fold charts, weak players would limp J8s from UTG because they “wanted to see a flop” or “felt like playing a hand.” Their VPIP would be 35, their PFR would be 8, and you’d know immediately they were a fish. Easy money.

Now? That same weak player downloads a decent pre-flop chart, sets up auto-fold, and suddenly their stats look like 27/22. They’re opening appropriate hands from appropriate positions. They look exactly like a competent regular.

But they’re still shit at poker. They just have a robot handling their pre-flop decisions.

Post-flop? They’re still making all the same mistakes. They’re still over-folding to aggression. They’re still not defending properly. They’re still playing scared, results-oriented poker. They’re still not exploiting anyone.

The auto-fold chart makes them look like a reg. The stack trajectory reveals they’re not.

The Real Tell: Stack Size After Volume

When you see a player with reg-like stats sitting on 100bb after 1000 hands, you’re looking at a losing player. They’re down 50bb or more from where they started, which means they’re losing at roughly 5bb/100.

If they have reg stats but they’re losing, what does that tell you?

It tells you they’re a shit reg. They know enough theory to open the right hands pre-flop (or they’re using auto-fold charts), but they don’t know how to actually win post-flop. More specifically: they’re getting exploited, and they’re not exploiting back.

The most common leak for shit regs is a declining red line. They’re losing big blinds without showdown, which means they’re over-folding to aggression. They’re getting bluffed off hands. They’re checking back when they should be betting. They’re folding when they should be calling or raising.

They look like regs. They play like prey.

Meanwhile, the player sitting on 160bb after 300 hands with similar stats? That’s a player who’s actually winning. They’re not just opening the right hands - they’re executing post-flop. They’re finding the bluffs. They’re applying pressure. They’re exploiting the pool aggressively.

They’re the real reg. And you need to know the difference.

The Three Types of Regs

The Shit Reg (100bb or less after 800+ hands, declining red line) This player looks solid on paper. Their VPIP/PFR suggests competence. But they're bleeding chips. If you could see their red line, it would be declining sharply. They're losing money without showdown, which means they're over-folding to aggression. They're the player who folds to your turn probe after they checked back the flop. They're the player who gives up when you triple-barrel. They're the player who never bluffs rivers. They know theory. They don't execute exploits. They're playing "correctly" by some GTO standard while the entire table exploits them. How to exploit: Attack them relentlessly. Probe turns when they check back flops. Triple-barrel when you sense weakness. ISO them liberally - they'll overfold post-flop even if they defend pre-flop. Don't bother with thin value bets - they're still folding too much. But bluff them constantly - especially multi-street bluffs. They can't handle sustained aggression.
The Solid Reg (120-170bb after 200+ hands) This is your competent opponent. Their stats look good AND they're actually winning. They're up 20-70bb, which suggests a win rate of 5-15bb/100. They're doing something right. These players are executing exploits properly. They're finding the folds. They're defending when they should. They're in the zone and playing good poker. Their red line is probably stable or slightly positive - they're not getting pushed around. How to play against: Respect them, but don't fear them. They're good, but they're not unbeatable. Play straightforward poker. Use your standard exploits. Don't get fancy. Don't try to level them. These are battles of execution, not creativity. If you're a better player, you'll win through superior fundamentals. If you're not, find a different table.
The Crusher (200bb+ after 1000+ hands) This player is destroying the pool. They're up 100bb or more after substantial volume, which means they're winning at 10bb/100 or higher. They're finding every exploit. They're not making mistakes. They're aggressive in the right spots and they're not getting pushed around. These players are rare, but they exist. And when you find one, you need to know it immediately. How to play against: Avoid them if possible. If you can't avoid them (it's fast-fold, they'll show up randomly), adjust heavily. Play tighter against them. Don't bluff them without good reason. Don't try to out-level them. Minimize your losses and wait for better spots against worse players.

Exploiting the Shit Reg

The shit reg is everywhere in fast-fold poker. They’re the majority of “regs” you’ll face at low and mid stakes. And they’re incredibly profitable to play against once you identify them.

The beauty is that they look exactly like solid regs if you only check their VPIP and PFR. But the stack trajectory gives them away instantly.

Here’s how to exploit them:

Attack with bluffs, especially multi-street. These players can’t handle sustained aggression. They’ll call the flop, then fold the turn. They’ll call the turn, then fold the river. They’ve been taught to “not pay off” and to “avoid marginal spots,” so they fold too much.

When you see a shit reg check back a flop, probe that turn relentlessly. They’re capped. They’re uncomfortable. They’re going to overfold. This is the empty room - walk through it.

ISO them liberally. When a fish limps and there’s a shit reg in the blinds, ISO wider than you normally would. The shit reg knows they’re “supposed” to defend, but they’re going to play fit-or-fold post-flop. You’ll win the pot on the flop or turn more often than you should.

Don’t value bet thin. Here’s the paradox: shit regs overfold to bluffs but they also overfold to value. They’re not calling down light. They’re not making hero calls. They’re playing scared. So your thin value bets don’t work as well as they should. Bluff them instead.

Triple-barrel with conviction. When you start a bluff against a shit reg, follow through. Don’t give up on the turn. Don’t check the river. They’re going to fold if you keep firing. They can’t stand the heat.

The shit reg with declining red line is a gold mine. They’re sitting there with their auto-fold charts, opening the right hands, and then bleeding chips post-flop because they don’t know how to actually play poker. They’re the fake regs. And they’re everywhere.

Close Decisions: Shit Reg vs. Solid Reg

This is where stack trajectory becomes invaluable. You’re facing a marginal decision, and you’re not sure if your opponent is a real reg or a fake one. Check their stack.

River Bluff Decision

You have a marginal bluff candidate on the river. Your opponent has 26/21 stats - looks like a reg. Do you bluff?

Check their stack:

  • 100bb after 900 hands? They’re a shit reg. Their red line is bleeding. They’re overfolds. Send the bluff.
  • 155bb after 250 hands? They’re a solid reg who’s executing well. They might be defending this spot properly. Check instead.

Same stats. Different stack trajectory. Different decision.

ISO Decision with QJs

Fish limps, there’s a reg in the big blind with solid-looking stats. You’re on the button with QJs. Do you ISO?

Check the reg’s stack:

  • 100bb after 700 hands? They’re struggling. Even if they defend pre-flop (they might, they’ve read that they should), they’re going to play scared post-flop. ISO liberally.
  • 170bb after 400 hands? They’re winning and probably defending well. Be more selective. QJs is marginal here - maybe just call and see a flop.

Turn Probe Decision

Reg opens, you call in position. Flop comes low and they check. Do you probe?

Check their stack:

  • 100bb after 1000 hands? Absolutely. They’re a shit reg who’s checking back too much and then overfolding to aggression. This is textbook empty room exploitation.
  • 145bb after 300 hands? They might actually be slow-playing or have a solid check-back range. Proceed more carefully.

The stack trajectory tells you whether you’re facing a real reg or a fake one. And that determines your entire strategy.

Secondary Profiles (The Others)

While the focus here is on identifying shit regs from solid regs, you’ll encounter other player types worth mentioning briefly.

The Heater (200bb+ stack, fewer hands played)

This could be a solid reg running hot, or a fish who’s hit some big hands. Either way, they’re confident and loose. They’ll defend wider, call lighter, and apply more pressure. Play straightforward against them - value bet when you have it, but don’t try to bluff them off hands.

The Maniac (40/35 stats at any stack size)

These are obviously exploitable. If they’re at 100bb after 1000 hands, they’re a spewy fish. If they’re at 200bb after 100 hands, they’re a heater having fun. Either way, call them down lighter and value bet relentlessly.

The Fresh Stack (100bb, <50 hands)

Unknown. They either just sat down or just reloaded. No assumptions yet. Play default strategy until you have more information.

But really, the game is about the regs. Because at fast-fold, especially at stakes like 50NL to 200NL, the majority of your opponents are going to be “regs” of some variety. And most of them are shit regs masquerading as solid ones.

Stack trajectory lets you see through the masquerade instantly.

The Aggressive Winner vs. The Timid Loser

Here’s the final insight: the player sitting at 150bb after 300 hands isn’t just winning - they’re winning aggressively.

Think about it. To build your stack from 100bb to 150bb in 300 hands, you need to be winning pots without showdown. You need to be taking down pots with aggression. You need to be bluffing successfully, applying pressure, and forcing folds.

This player’s red line is probably climbing. They’re winning chips through aggression, not just by waiting for big hands and getting paid. They’re the predator.

Meanwhile, the shit reg at 100bb after 1000 hands? Their red line is bleeding. They’re losing chips through passivity. They’re checking when they should bet. They’re folding when they should call or raise. They’re the prey.

Same stats. Completely different mentalities. Completely different results.

The aggressive winner is attacking empty rooms. The timid loser is getting attacked in theirs.

You want to emulate the former. You want to exploit the latter.

Traditional HUD stats are like reading someone’s resume. You see their qualifications, their general approach, their style on paper. Stack trajectory is like looking at their face right now - are they winning or losing? Are they confident or scared? Are they aggressive or timid?

In fast-fold poker, where auto-fold charts let weak players masquerade as competent regs, this real-time information becomes critical. A 27/22 stat line means nothing without context. But a 27/22 at 100bb after 1000 hands? That’s a shit reg with a declining red line who’s getting exploited post-flop despite playing “solid” pre-flop.

That’s a player you attack relentlessly.

The best players don’t just look at stats. They synthesize every piece of available information - stack size, hands played, bet timings, table dynamics - into a complete picture of who’s actually winning and who’s just pretending to be a reg.

Most “regs” at your stakes are shit regs. They look competent. They have reasonable stats. They might even talk a good game. But they’re bleeding chips because they don’t execute exploits. They play scared. They overfold. Their red lines are declining.

Stack trajectory reveals them instantly.

The information is sitting right there on your screen. Most players never even glance at it. They see 26/20 stats and assume they’re facing a solid opponent.

You can be different. You can see through the masquerade.

And you can exploit them mercilessly.