Top 5 powers of Mjolnir

5. It can absorb and redirect energy, exactly like it did against Kang the Conqueror.

4. It can create storms and control the weather, like when Jane Foster wielded it and created a storm to stop the frost giants.

3. It can open portals; Thor used this power to find Loki.

2. When thrown, it comes right back to it's user and can be controlled by the welder’s mind.

1. Mjolnir's top power, in my opinion, it that it can time travel.

There's been lots of different wielders of Mjolnir, but the most well-known, Thor, is by far the strongest of these owners.