Нічия краща, ніж поразка.

Because краща has to agree with нічия, which is a feminine singular noun.

• нічия = feminine singular
• so the comparative adjective also becomes feminine singular: краща

Compare:

• поразка краща — feminine
• результат кращий — masculine
• місце краще — neuter

For English speakers, this is different because better never changes in English, but in Ukrainian it does.

Also, краще is very often used as an adverb or in neuter/impersonal structures:

• Вона грає краще. = She plays better.
• Так краще. = That’s better.

But here better describes the noun нічия, so краща is the right form.

In Ukrainian, the verb to be in the present tense is usually left out.

So:

• Нічия краща, ніж поразка.

literally looks like:

• Draw better than defeat.

But it naturally means:

• A draw is better than a defeat.

This is completely normal Ukrainian grammar. English needs is here, but Ukrainian usually does not.

Both are in the nominative singular here.

• нічия is nominative because it is the subject.
• поразка also stays nominative after ніж in this kind of comparison.

This is useful to compare with other comparison patterns:

• Нічия краща, ніж поразка. — ніж
  • nominative
• Нічия краща за поразку. — за
  • accusative
• Нічия краща від поразки. — від
  • genitive

So the sentence is a good example of one common comparison pattern in Ukrainian.

Ніж means than in comparisons.

So:

• краща, ніж поразка = better than defeat

It is used after a comparative form like:

• кращий / краща / краще
• гірший / гірша / гірше
• більший / більша / більше

Examples:

• Це краще, ніж учора.
• Він вищий, ніж брат.
• Поїзд швидший, ніж автобус.

So in this sentence, ніж simply introduces the thing being compared.

Yes. Ukrainian has several ways to say than in comparisons.

All of these are possible:

• Нічия краща, ніж поразка.
• Нічия краща за поразку.
• Нічия краща від поразки.

The meaning is basically the same, but the grammar changes:

• ніж
  • nominative: поразка
• за
  • accusative: поразку
• від
  • genitive: поразки

For a learner, ніж and за are especially useful and common.
This sentence uses the ніж pattern.

Because ніж is treated like a conjunction introducing the second part of the comparison, and in Ukrainian that part is normally separated by a comma.

So:

• Нічия краща, ніж поразка.

That comma is standard.
English usually does not require a comma in better than defeat, so this is something English speakers often notice.

It can mean something else too, and that can confuse learners.

In this sentence, нічия is a noun meaning a draw / a tie.

But нічия can also be the feminine form of нічий, meaning nobody’s / no one’s.

So compare:

• Нічия краща, ніж поразка. — нічия = a draw
• нічия сумка — no one’s bag

In your sentence, it is clearly the noun because it stands alone as the subject.

Yes, Ukrainian word order is more flexible than English, because the endings carry a lot of the grammar.

The most neutral version is:

• Нічия краща, ніж поразка.

You may also see:

• Краща нічия, ніж поразка.

That version sounds more emphatic, almost like a saying: Better a draw than a defeat.

So yes, word order can change, but for learners the original version is the safest neutral pattern.

Because Ukrainian has no articles.

So нічия can mean:

• a draw
• the draw
• or just draw in a general sense

And поразка can mean:

• a defeat
• the defeat
• or defeat generally

Context tells you which one is meant. In this sentence, it is most naturally understood as a general statement.

They are close, but not always identical.

• поразка = defeat
• програш = loss, losing

Поразка often sounds a bit broader or stronger, and is very natural for sports, competitions, battles, campaigns, and figurative failure.

Програш often focuses more directly on the fact that someone lost a game, bet, or contest.

In this sentence, поразка sounds very natural and idiomatic. It gives the idea that a draw is preferable to outright defeat.