T2 Heavy Tanks are heavy tank type units which are tougher and more powerful than their lighter counterparts, existing in T1. The UEFPillar, CybranRhino, and AeonObsidian, which all have quite a bit of diversity compared to other types of units
Their general role is typically to be the mainstay land unit of each of the respective factions, and with this in mind, none of them are amphibious. They all possess good DPS, good Hit points and average speed. While the UEF and the Cybran tanks are comparable, the Aeon tank is quite a step up from either of them - costing twice as much, and being approximately twice as good.
The UEF's Heavy Tank is the Pillar - it has the most hp (although the Obsidian can take more of a beating due to its shield). It has a high firing arc, making terrain less of a problem (leading to a higher Effective DPS). It fires two projectiles at a time, leading to a marginally higher chance of hitting with at least one of them, but its projectiles can take a short time to reach the target - occasionally causing them to miss when another, quicker weapon would not have. The UEF are in an almost unique position, where they have two highly usable units vying for the same spot - the Pillar and theMongoose. Typically, players appear to prefer the Mongoose due to its higher manoeuvrability - making it better served to the backwards and forwards nature of the early to mid game. The Mongoose also has a longer range, better line of sight and more firepower (albeit at a cost of some health). This means that since its addition, the Pillar has seen less and less use.
The Cybran's Heavy Tank is the Rhino and it features a very capable gun which hits instantly, unlike the UEF's projectile weapon. In open terrain, its rapid fire and instant hits minimize overkill, and combined with its higher DPS it is more effective against crowds of units. Rather unfortunately it has a firing arc that is easily blocked by low hills, lowering its effective range (and effective DPS), and often giving a player who is fielding an army of Pillars a distinct advantage - as it will usually take the player a few seconds to realize that their shots are not hitting, and a few more to compensate. In addition, the Rhino's health is disproportionately less than the Pillar's, making it unsuited to one on one duels.
The Aeon's Heavy Tank is the Obsidian - and when compared to the other two Heavy Tanks here, it is in a league all of its own. Its DPS is in a league all of its own - dealing 480 damage per shot, it is not great at tackling T1 Units. It has the highest one-shot damage of any T1 or T2 land unit, and can survive well into T3 due to its shield and good initial shot damage. Notably however, the Aeon player may choose not to go with the Obsidian and instead to side with the Blaze. It's cheaper, faster, with a longer range and more health (albeit, with less overall damage absorption potential, as it has no shield). It also builds in approximately half the time, and can hover - often an important aspect to an early Aeon "Land" Army on water maps. This allows for maximum manoeuvrability, and can often allow an Aeon commander to press an attack over open water, following an Aurora assault.