isolation
ActionAliases: isolation raise, iso, 隔离, 孤立加注
An isolation raise is a slightly wider raise after a weak player limps, designed to peel off a heads-up pot against the limper — the core tool for attacking limpers.
An isolation raise (iso) is a raise after one or more players have limped into the pot, using a slightly wider range than a standard open. The goal is to fold out the players behind you and create a heads-up pot with the limper.
Detailed Explanation
Why an iso uses larger sizing than a standard open:
- Larger starting pot: the limper has already put in 1bb, so you're raising into a bigger base
- Need to fold out players behind: players behind a limp + raise are more likely to fold than against a single open
- Targeting a weak range: the limper's range is usually weak and passive, so post-flop cbet frequency is high
Standard iso sizing: standard open + 1bb per limper. Example: 3bb standard open + 1 limper → iso to 4bb; 2 limpers → 5bb.
The iso range is wider than a standard open because:
- You face the limper's weak range, naturally giving you an equity edge
- In a heads-up pot you'll have position (if the iso seat acts after the limper)
- Postflop cbet fold equity is high
In practice, BTN against an MP limper can iso 30%+ of hands — much wider than BTN's standard open (25%).
Common Use Cases
- Single limper ahead of you: BTN/CO iso wide
- Multiple limpers ahead: tighten the iso range — multi-way pots reduce cbet effectiveness
- Aggressive player behind the limper: iso carefully — you can be cold 3bet
- Table with widespread limping: iso is a stable +EV source