The Hover Tank is the heavy military unit of the Future Era. It is unlocked through the Gravity Fields, and is the second unlocked unit of the Future Era. It is trained in the Hover Tank Base and it can also be received by completing the Greetings from a Friend and Business in Bisoraba Story Quests.
Compared to the Stealth Tank, the Hover Tank gains 15 defense and has greatly improved range, though attack stays the same and movement is decreased (but it is able to pass through water tiles). Bonuses against ranged units are increased greatly, though against fast units, it is decreased slightly (and is negligible). It keeps the Stealth ability on plains, but also gains a new Force Field ability, taking two less hit points of damage per attack to a minimum of one.
The Hover Tank is a massive improvement from the Stealth Tank, owing to it's greatly increased range, which the Stealth Tank clearly lacked. In addition, the Hover Tank's Force Field ability can prevent it from taking serious damage especially from artillery units that can attack the Hover Tank hiding on Plains, and it can usually reach from one end to the battlefield and attack units in other end in two turns as well.
Its ability to pass through water tiles is highly situational, as some maps have barely any water tiles (or even no water at all), but on maps with a lot of water it can make a signifcant difference. However, in manual combat it can be exploited by a skilled player by getting enemy Hover Tanks to stand on the water, thus losing their stealth.
It can be used as a higher era unit as well, and it is extremely powerful against all units in the Contemporary Era and below. It can also attack units with the Contact! ability such as the MG Team, Anti-Aircraft Vehicle and Ultra AP without fear of retaliation, due to its superior range, and can easily be used to auto-battle fights in Guild Battlegrounds and even in Level 4 Guild Expeditions, without fear of much damage to your real Hover Tank if paired with rogues.
However, the biggest threats to the Hover Tank are artillery units, as they can generally ignore the Hover Tank's Stealth ability, and units from higher ages as well, though the Hover Tank still remains effective as long as you have a sufficiently strong army boost. Also note that, like the Stealth Tank, it is better to skip an attack than to become visible and attack the enemy. Without Stealth, the Hover Tank will become a vulnerable target.
Against Same Age Units
The Hover Tank is the best counter to the Satellite Spotter, as the Hover Tank can easily hide over their long range. Their great bonuses against ranged units means that they can easily kill Satellite Spotters, and when Satellite Spotters attack Hover Tanks, they will do usually do incredibly little damage (thanks to the Hover Tank's Force Field ability), and suffer a terrible retaliation.
Although the Hover Tank has bonuses against fast units, combined with their Stealth ability, this is usually negligible when fighting Drone Swarms, as their bonuses against fast units are tiny and Drone Swarms are melee units. Despite this, the Hover Tank is very efficient at killing Drone Swarms, as long as they are not located in forests or houses. As Drone Swarms are melee units, they will have to receive retaliation for their attacks. However, the Drone Swarm can often deal somewhat considerable damage to the Hover Tanks, even though the Hover Tank has the Force Field Ability.
The Exoskeleton Soldier is one of two counters to the Hover Tank. They have high bonuses against heavy units and the Blast ability to ignore their Stealth, so Hover Tanks are immediately vulnerable to them. The Hover Tank cannot generally damage the Exoskeleton Soldier effectively, but the Hover Tank's Force Field ability can often prevent Exoskeleton Soldiers from dealing too much damage. They are generally not a big problem as long as you have a good enough attack and defense boost, however.
The Rail Gun is the other counter to the Hover Tank. Unlike previous age artillery units, the Rail Gun has an exceptionally long range and very high attack and defense as well as bonuses against heavy units and the Power Shot ability, so they can ignore the Stealth ability of the Hover Tank and deal a lot of damage to them, even with the absorbed hit points. However, the Rail Gun can only fire once every two turns, so that often means that the Hover Tank can still deal a lot of damage to them whilst they are reloading, but it will be severly hindered by the very high defense of the Rail Gun.