Use E for Regenerate in Portal Sandbox. The official experience description confirms the key and action name, but it does not publish a recovery amount, cooldown, resource cost, full-health behavior, death restriction, or invulnerability period. Test the action only when the current state makes its result visible.
Prepare a useful recovery test
First verify that you are in the correct experience at Place ID 75108253383447. Move away from a portal transition, close chat or menus, and identify the state you expect Regenerate to change. If a health display or character condition is visible, note it before pressing E.
Press E once and watch for a value, animation, effect, sound, message, or state change. Wait long enough to see the current feedback before pressing again. A test at full health or during an unclear transition may produce no obvious change and should not be treated as proof of failure.
Keep Regenerate separate from other tools
Portal Gun is on T, Blender Dimension is on F, Dimensions is on R, Mech Blaster is on X, and Robo Arms is on V. Do not swap through all of them while testing Regenerate. A single-action test tells you whether E reached the recovery system or whether another UI captured the input.
In PvP, another player can damage or interrupt you while the action is being observed. Reproduce the result in a quieter area. If it works there but not in a fight, record the combat state rather than calling the keyboard binding universally broken.
Do not assume hidden numbers
The word Regenerate suggests recovery, but the public official description supplies no exact value. Do not claim that it always restores full health, has a fixed cooldown, removes a condition, revives a defeated player, or creates invulnerability without current evidence.
If the live game displays a number or timer, treat it as a dated current-build observation. A beta update may change it. The Updates hub records public update timestamps but does not convert them into patch details that the developer did not publish.
Troubleshoot Regenerate not working
Close chat and any text input. Confirm the game window has focus. Move away from a portal crossing or dimension transition. Create an observable state without deliberately risking valuable items, press E once, and compare before and after. Rejoin once if the action state appears stuck.
If nothing changes, record whether you were already full, recently defeated, in a menu, switching tools, or being attacked. Include the device and visible action label. On mobile or controller, report the actual on-screen control rather than assuming the keyboard letter should appear.
The experience is explicitly labeled beta, so a repeatable issue may be real. A useful report states the shortest sequence and result. Do not use an executor, paste unknown scripts, or give anyone your password, login code, recovery key, or session cookie.
Use Regenerate in a session plan
Learn the action outside PvP first. During freeroam or portal practice, use a safe observable moment to confirm the current behavior. During PvP, decide whether you have enough separation to test recovery without confusing incoming damage with an incomplete result. Keep a return route available if portal movement is part of the plan.
The official Store includes an Insurance pass whose description discusses keeping items through three deaths before a fourth drop and reset. That product text shows that death and item handling matter, but it does not define Regenerate or prove that recovery prevents item loss. Keep the systems separate unless the live game explicitly connects them.
Compare device behavior carefully
The developer states all-device compatibility and no VR support. Exact mobile button placement and controller bindings were not published in the public description. Find the action name in the live interface and test the same observable before-and-after state.
If one device behaves differently, record the device class, screen orientation when relevant, visible control label, and whether another interface overlaps it. Avoid turning one device result into a universal rule.
Regenerate questions
What key regenerates in Portal Sandbox?
The current official keyboard control is E.
Does Regenerate restore full health?
The official public description does not state a recovery amount. Confirm the current result in game.
Why did E do nothing?
Check whether you were already full, chat or a menu had focus, a transition was active, or combat interrupted the action. Repeat the shortest test in a quiet area and rejoin once if needed.
Does Regenerate protect items on death?
No such connection is stated in the public control description. The Insurance game pass has its own item-retention wording and should not be confused with Regenerate.