Could the Mongols defeat all the armies and conquer all europe?

As you know, Subeedei and Batu khans troops already defeated Polish as well as Hungarian army in battle at Sajo River , when they stopped by the news of Ogedei (was Great khan in Khara-Khorum, son and successor of Chingis Khaan) khans death.

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The yasaq explicitly provided that after the death of the ruler all offspring of the house of Chinggis Khan, wherever they might be, must return to Mongolia to take part in the election of the new khan. From the outskirts of Vienna and Venice, the tumen countermarched, never to reappear
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Do u think if they continued their expansion into european land, destroy all the armies and conquer all Europe?

If they continued their conquest they would destroy any army but if you take a look at Mongol history they didn't  hold their lands for a long time therfore I think they would lost Europe quickly.

Not only that, but China was both very close, and very worth the effort.

what the hell you ever talk about?

1. what "great european fortresses"???? do you seriously think any 13th century european fortress can be compared anywhere near the massive city wall of Xinyang or the well situated castle fortress of Alamut?

2. what big european forces? Fredericks army was occupied in Italy with the Pope and as most european forces was rpedominantely composed of kngihts, just liek the armies of Poland and Hungary, and what crossbowmen? CHina had thousands odf them and certainly more disciplined.

3. what great european forrests? i live in the center of europe and know how these forrests look like, do you think they can be even compared to the vegetation in southern china???

Unlike other mobile fighters such as the Huns or the Vikings, the Mongols were very comfortable in the art of the siege. They were very careful to recruit artisans from the cities they plundered, and along with a group of experienced Chinese engineers, they were expert in building the trebuchet and other siege machines. These were mostly built on the spot using nearby trees.

Another advantage of the Mongols was their ability to traverse large distances even in debilitatingly cold winters; in particular, frozen rivers led them like highways to large urban conurbations on their banks. In addition to siege engineering, the Mongols were also adept at river-work, crossing the river Sajo in spring flood conditions with thirty thousand cavalry during one night during the battle of Mohi (April, 1241), defeating the Hungarian king Bela IV. Similarly, in the attack against the Khwarezmshah, a flotilla of barges were used to prevent escape on the river.