For a player who wants a heavy tank that can be reached through the live World of Tanks Blitz Tech Tree, start with the IS-7 or E 100 rather than a time-limited Store offer. They are not interchangeable, and neither is permanently the best for every map or player. The IS-7 is the stronger fit for a commander who wants faster forward movement and a more regular firing rhythm. The E 100 fits a player who accepts a slower, more deliberate heavy in exchange for a much larger single hit.
This comparison uses the live BlitzKit Tankopedia, which identifies both vehicles as Tier X Tech Tree heavies in the production client. Wargaming’s own Blitz support guide explains the route: research the preceding modules and vehicles in the Tech Tree, then buy the researched tank for credits. That distinction matters. Event tanks may be interesting when available, but a permanent research route is a better basis for a long grind recommendation.
Best first Tier X Tech Tree heavy: IS-7
The IS-7 is the more forgiving starting recommendation for players who want a conventional breakthrough heavy with enough speed to reach a useful lane. BlitzKit lists it as a Tier X Soviet Tech Tree heavy reached through the KV-1, KV-1S, IS, IS-3, IS-8, and then IS-7 route. Its current profile lists a 130 mm gun, 460 standard damage, 251 mm standard penetration, a 10.67-second reload, 40 km/h forward speed, and 2,550 hit points.
Those numbers explain the role. Forty km/h is quick enough that the IS-7 should make an early decision about the heavy lane or a central support position instead of trailing the team. The 10.67-second reload calls for a steady trading rhythm: fire after an opponent exposes, retreat while reloading, then return when your gun is ready. A 460-damage hit is meaningful, but it does not excuse taking two or three return shots for one.
Play the IS-7 as a forward heavy that still respects crossfire. Move with at least one ally, use hard cover to break line of sight after shooting, and keep the hull generally pointed toward the enemy when you expect a return shot. On a corridor map, this can mean taking the first protected corner and making opponents shoot into a prepared front. On an open map, use its speed to arrive at cover, not to drive across the middle alone.
The current 6-degree gun depression is a limitation worth planning around. A steep ridge can force the gun upward or expose too much hull. Pick shallower rises, rubble, buildings, and corners where the gun can work without needing a perfect hull-down position. The 13 km/h reverse speed also means an ill-considered push is not instantly reversible. Leave a retreat line before committing to a narrow street.
Choose IS-7 if you value position-taking, a regular gun cycle, and a relatively direct brawling plan. Its route makes sense for a player who wants a repeatable Tier X heavy style rather than a special mechanic or a temporary purchase.
Best for high-alpha trading: E 100
The E 100 is the better recommendation for a patient player who prefers big, deliberate exchanges from cover. BlitzKit lists it as a Tier X German Tech Tree heavy on the Tiger I, Tiger II, E 75, E 100 route. The live profile shows a 150 mm gun with 645 standard damage, 254 mm standard penetration, a 15.92-second reload, 30 km/h forward speed, 12 km/h reverse speed, 7 degrees of gun depression, and 2,750 hit points.
The first decision with E 100 is whether a shot is safe enough to justify its long reload. A 645-damage hit can make an opponent hesitate, but the 15.92-second reload creates a real period of vulnerability. Do not trade merely because the gun is loaded. Wait for an enemy to fire, a teammate to draw attention, or a position where hard cover is available immediately after the shot. The tank is more effective in a controlled corner fight than in a wide open exchange where several guns can punish the reload.
Its 30 km/h top speed reinforces that plan. Go to the side of the map where heavy armor and cover will decide the fight, then arrive in time rather than trying to react to every developing skirmish. Once there, use buildings, wrecks, and terrain to reveal the gun briefly and conceal the rest of the vehicle. The 7 degrees of gun depression can help on moderate terrain, but do not confuse that with a license to crest every ridge; check who can shoot the hull before exposing.
Choose E 100 if a slower tempo suits you. It rewards a player who can count reloads, avoid unnecessary exposure, and make a large hit matter. It will feel frustrating for someone who wants to relocate often or fire repeatedly while moving with medium tanks.
How the two routes differ
| Need | Better starting choice | Why |
|---|---|---|
| Reach the important lane sooner | IS-7 | Its listed 40 km/h forward speed is higher than E 100’s 30 km/h. |
| Fire more often | IS-7 | Its listed 10.67-second reload is shorter than E 100’s 15.92 seconds. |
| Make larger single-shot trades | E 100 | Its listed 645 standard damage exceeds IS-7’s 460. |
| Prefer a long, permanent grind route | Either | Both are currently labelled Tech Tree vehicles, not event-only offers. |
These facts do not establish a universal meta ranking. They establish a useful style choice. The IS-7 asks you to use pace and repeated trades. The E 100 asks you to preserve hit points during a long reload and punish opponents with larger shots.
Build and play the heavy around its weaknesses
Before researching the final vehicle, play the preceding tanks long enough to decide whether the line feels natural. Wargaming’s Tech Tree guide notes that modules must be researched before the next vehicle becomes available, so rushing past the intermediate tanks without learning their map positions often creates an expensive Tier X disappointment. Use the in-game comparison screen to check the current module configuration, equipment choices, and ammunition before buying.
In battle, do three things consistently. First, identify the lane where cover lets a heavy face one threat at a time. Second, trade only when your team can return fire or when the opponent has just fired. Third, preserve health for the final two minutes, when a heavy’s hit points and gun become more valuable than an early, risky damage number. Do not lead a charge into an unseen crossfire simply because the tank has armor.
For a reachable recommendation, choose IS-7 when you want the faster, regular-gun route and E 100 when you want the slower, high-alpha route. Confirm their current values in the production client before committing credits or Free XP, because Blitz balance changes can alter details without changing the basic role comparison.