Tiger 1

The Tiger I, aka the Panzerkampwagen VI Ausf. E was a German heavy tank during WWII. When most people hear about German Tanks during WWII, this beast is usually what comes to mind first. A 54 tonne brick shithouse packing a massive 88mm cannon, it could be a nightmare for allied tanks to face. It was also slow, expensive, ponderous and had a lot of mechanical issues.

IRL

The Tiger I was developed after the Battle of France after it was found that the Panzer III had insufficient performance against the French Char 1B battle tanks and the British Matilda. Flashback to 1937, where several German arms firms were working on ideas for a heavy tank. This is the earliest origins of the Tiger I.

Speed forward to Operation Barbarossa, where the German high command learned that their master race tanks were worthless against the T-34 and the KV-1. Thus, the Tiger I was rushed into service, chosen in preference to Porsche's shitty Ferdinand design. The Tiger was rushed into service, both in Africa and on the Eastern front. The Tiger earned fame in both theaters, resulting in the western allies throwing better guns into their existing vehicles, and the Soviets logically deciding to try to just build their own bigger and better tanks.

The Tiger was an absolute unit, being immune to all but the most powerful AT weapons, with close air support and artillery being the most efficient way to kill them save hoping a bigger tank or weapon is nearby. It had an 88mm KWK 36 at gun, which could kill most operational tanks during the war, and the addition of several MG 34s were effective deterrents to infantry rushes.

In spite of all this, the Tiger had it's flaws. It was super heavy and prone to mechanical problems and guzzled gas. Therefore, its greatest enemies were long distances, bridges, and breakdowns. It also had a massive profile, and failed to incorporate the advantages of sloped armor into its design. This made it vulnerable to more advanced AT guns. Compounding this, its large size made it target practice for Ground attack aircraft and dedicated field artillery.

In spite of these terrible shortcomings, the Tiger earned it's reputation as a terribly effective weapon if deployed in the right place. In one case, a single Tiger took on a fuckload of Shermans and knocked all of them out of action with minimal damage sustained. For this reason they were kept on until the end of the war.

Interestingly, the designers of the tank were acutely aware of the fact that it was too heavy. So as a possible solution, the vehicle was designed with the ability to ford relatively shallow waters in which the entire vehicle is submerged, with a snorkel system feeding air to the engine and the entire crew compartment being sealed. The complexity of this system meant that it was abandoned shortly after the first tanks rolled off the assembly lines in order to get them off the production lines faster, but it was incredibly interesting nonetheless.

It spawned a spinoff design, the Sturmtiger, which is functionally a Vindicator that shot big fuckoff rockets and had so much frontal armor that even a Baneblade would tip its hat to it. It was primarily used as a heavy siege vehicle against pesky defensive structures like Pillboxes, or to cause collective existence failures to Communist IS-2s and KV-1s.