Alpha Man

Alpha Man is a humorous Roguelike game set in a post-apocalyptic New York. The main character has powers, the berries give special effects, and the creatures are varied and humorous, from "Prairie Chickens" to "Snails" that assault the player's brain and "Purple Mold" that makes the player sick. It is Shareware.

It has a wiki.

Download it here (you'll need DOS Box or something similar if you can't run DOS programs normally).

Some tropes used in the game:
 * Blind Jump: Don't teleport into a wall, and don't teleport to a place if there even might be a wall there. You won't get a second chance.
 * Bottomless Bladder: You eat, you drink... but you never need the restroom, even though a Porta Potty exists in-game (and is as disgusting as you might assume).
 * Everything Trying to Kill You: Everything. You can die by overeating, by being struck by lightning, by using a suicide machine....
 * Goddamned Bats: Grey Mold, Dung Beetles
 * Gotta Catch Them All: The game has several items you have to gather before you can go to the main stronghold. Some are optional, if you're lucky or prepared enough.
 * Hit Points
 * Insurmountable Waist Height Fence: Averted when using the Jackhammer, but you still can't move outside the larger game map.
 * It's Up to You: Yeah, the game makes an attempt to lead you through the plot, but you don't have to follow what it recommends.
 * Mr. Exposition: The tape recorders.
 * One-Man Army: Around level 10, you start being able to take down Tyrannosaurs...
 * The Many Deaths of You: Died by exploding berry. Died by using a Kevorkian machine. You can even be killed by your own clothes if you wear a Neutron Suit...
 * Twenty Minutes Into the Future
 * Schizo Tech: It's not uncommon to be wielding a laser pistol, wearing plate mail, and spraying down hostile mold with Mr. Clean...
 * Super Drowning Skills: Averted. The player can survive falling into water until he's too tired to swim and passes out, at which point he drowns.
 * Vendor Trash: Averted. There are no stores, and no place to sell useless items.
 * The Very Definitely Final Dungeon: The Grinch's castle, of course.
 * Weapon of Mass Destruction: The Tickle Feather Gun. Seriously. Also, more predictably, the Disintegration Grenade.
 * Wizard Needs Food Badly: Your character survives on Spam and Beef-A-Roni, and dies if he goes without eating too long. Note that the entire game takes place over seven days--during which time anybody should be able to survive without eating. Maybe the mutations force your character to eat a lot?