He's not averse to taking a dizzying punch to the head if he can score a point. Rights groups accuse him of using armed squads to abduct suspected separatists. His party's program, somewhat improbably, calls for nuclear rearmament of Ukraine.
But no matter how outrageous his antics and program seem, firebrand politician Oleh Lyashko strikes a chord among many in a population pushed to extremes by war. Polls suggest he will be a political wild card whose support President Petro Poroshenko may reluctantly have to seek after next Sunday's election
In an interview in Kiev, Lyashko, a wiry figure with a voice like a foghorn, saw his party gaining a big enough share of the vote to make him a power broker in a new-look assembly.
"I am the kingmaker," the 41-year-old former journalist said, predicting a vote of 15-20 percent for his party — although opinion polls put it at up to 12 percent.
Next Sunday's election — the first to parliament since the "Euromaidan" winter protests overthrew the Moscow-backed Viktor Yanukovych and set in train a geopolitical crisis around Ukraine — takes place amid confrontation with Russia and a separatist war that has killed more than 3,700 people.
Many Ukrainians have become radicalized by a conflict that has brought death and hardship to homes across the country.
The opportunity has not been lost on Lyashko who, until a year ago, was a lone eccentric in parliament largely ignored as he defended the rights of small businesses, spoke up for higher pensions and social benefits and fulminated against big industrial 'oligarch' money.
Tapping into voter anger over hardship from the war, the fast-talking Lyashko has morphed into a fierce defender of volunteer fighters and their bereaved families, and a critic of Ukraine's super-rich who he suggests are playing their own political games while others die.
His party emblem is a three-pronged pitchfork — the Ukrainian peasant's traditional tool of protest and defense, and symbol of his declared determination to jab his enemies. He says he wants to clear the oligarchs out of politics.
Ukraine's super-wealthy come only second to Russia's Vladimir Putin on Lyashko's 'anger list' as he speaks up for the fighters at the front and preaches a bellicose agenda of confrontation with Russia and no loss of territory to the separatists.
"Putin cannot be trusted. It is a catastrophic mistake and miscalculation to count on what Putin promises. Today he speaks and tomorrow he forgets," he said in the interview, slipping into the hectoring tone he uses when out on the stump.
"We have to be strong so that Putin won't come at us because he will know that he will lose," Lyashko said.
In the past, he has been a fighter for the rights of small business in Ukraine. But a constituency he is eyeing now for support are the volunteer militia groups — "the real patriots", he calls them — who are fighting with government forces against the separatists.
Last week he announced establishment of a help center for invalided fighters and bereaved families, oversaw presentation of a free apartment to a war widow and children and named a volunteer battalion commander as No. 3 on his party list.
He is not afraid of pulling the odd risky stunt to gain attention — something which has brought him comparison with Russia's political showman Vladimir Zhirinovsky.
In August — under the glare of television cameras — he took a punch in the face that left him groggy after he called a fellow parliamentary deputy a "pot-bellied fatty" and accused him of ignoring the plight of soldiers on the front.
Promotional video clips, though, which show him berating and humiliating separatist suspects who are bound and held by his men, show a darker side and have brought him condemnation by human rights groups.
One notorious video shows him interrogating a bound and semi-naked man who admits to being a former 'minister of defense' of the self-proclaimed People's Republic of Donetsk. He is dressed only in underwear with visible cuts on his body.
The rights group Amnesty International last August accused Lyashko of "detaining — in effect abducting — and ill-treating individuals across the region ... while the camera is rolling."
Despite his past role as a perennial marginal, he surprised many last May when he came third in the election for president. Opinion polls appear to show that his confrontational, populist style is finding support at grassroots level where traditional nationalist parties like Svoboda (Freedom) are failing.
Poroshenko, a 49-year-old confectionery magnate, won election as president by a landslide. Most polls now give Poroshenko's bloc roughly 30 percent of the vote on the party lists which account for half of the 450 seats in parliament.
These polls see Lyashko's Radical Party getting anywhere between 7 to 12 percent of the vote on party lists with roughly the same level of support for the Batkivshchyna (Fatherland) party of former prime minister Yulia Tymoshenko.
Tymoshenko, the former nemesis of the disgraced Yanukovych who jailed her until the 'Euromaidan' protests chased him from power in February, is running a low-key campaign after several defections by former allies.
On the basis of the opinion polls she and her party are also assured of a presence in parliament. But she and Poroshenko are old adversaries from the time they both served under former president Viktor Yushchenko and most analysts say he would not trust her in any political deal.
That means that if Poroshenko falls short of an outright majority his bloc may be looking to Lyashko's party as a stable-mate in any coalition to form a strategy for ending the war and pushing through reforms to meet a pro-Europe agenda.
In the interview, Lyashko said Poroshenko now accepted he would be a force to be reckoned with in the next parliament and had already offered him the powerful post of parliament Speaker.
Lyashko said he had turned down the offer because he wanted the post of prime minister to "radically change the economic situation in the country." Poroshenko's reported offer could not immediately be confirmed by the presidency.
Lyashko said he did not rule out throwing his party's support behind a pro-Poroshenko coalition. But his angry criticism of Poroshenko's peace plan to end the fighting in the east suggests this might be no easy relationship.
Referring to the 70 or so government soldiers killed since a cease-fire came into force on Sept. 5, Lyashko denounced the "illusion" of peace in the east. "We will never agree to giving up territory, to Putin's plan. Poroshenko today is virtually realizing Putin's plan for Ukraine," he said.
Of his party's commitment to renewing "the nuclear status" of the country, he said Ukraine had made a historic mistake in returning nuclear weapons to Russia when the Soviet Union fell.
He said Russia's armed intervention had shown that Ukraine needed "real security guarantees".
"It is realistic (for Ukraine to acquire nuclear arms) from a technical and scientific point of view, but very improbable given the pressure from the international community," he conceded.