Dota 2/Slardar the Slithereen Guard

Slardar is a melee strength hero who can be played as a semi-carry, a support or a ganker. He has skills that help him chase down and weaken his foes. His Slithereen Crush is a reliable AoE stun that can be spammed in teamfights. His Sprint is basically a free Haste rune useful for chasing down enemies, though it is dangerous to use when there are other enemies as he takes more damage. His Bash can pin down enemies, letting him reach the damage output of carries. The main reason Slardar is picked is arguably because of his ultimate: Amplify Damage. Being very spammable, it can turn the most tanky heroes into a fragile weakling. It also makes Slardar the bane of invisible heroes, as it can track them down no matter how far they run.

Sprint
Sprint grants you bonus movement speed, but makes you take more damage from enemy attacks. It is an ability best used outside of teamfights, where you have less chance of being targeted by multiple enemies. The increased movement speed is great for rushing to a push or teamfight without a TP Scroll. It can also be used to chase down enemy heroes when ganking.
 * Ability: No Target
 * Additional Damage: 15%
 * Bonus Speed: 20% / 27% / 33% / 40%
 * Duration: 20
 * Mana Cost: 50
 * Cooldown: 40

Slithereen Crush
Slithereen Crush stuns and deals damage to enemies around you as well as slowing them afterwards. It has a low cooldown, which makes it very spammable. It is a great way to hold multiple heroes in place as you and your allies shred them. The slow also makes it hard for them to escape after getting crushed. Duraing teamfights, you should spam it very often, so that you can keep stunning multiple enemies and help your teammates finish them off.
 * Ability: No Target
 * Damage Type: Physical
 * Damage: 50 / 100 / 150 / 200
 * Radius: 350
 * Slow: 20%
 * Slow Duration: 2
 * Stun Duration: 1 / 1.5 / 2 / 2.5
 * Mana Cost: 80 / 95 / 105 / 115
 * Cooldown: 8

Bash
Bash makes your normal attacks to have a chance to stun your target for 1 second, 2 seconds on creeps, as well as doing bonus magical damage. Although it isn't very impressive until your attack speed gets high enough, it can let you match the dps of carries. The stun is a great way to hold enemies in place, and if you're lucky you can actually stun-lock them as you chip away their health.
 * Ability: Passive
 * Damage Type: Magical
 * Chance: 10% / 15% / 20% / 25%
 * Bonus Damage: 40 / 50 / 60 / 70
 * Duration: 1

Amplify Damage
Amplify Damage reduces the armor of the target as well as granting True Sight on it wherever it goes. With its low cooldown of ten seconds it can be used often. As a result, it can reduce the durability of well-farmed carries down to the level of weak supports. Inflicting it on multiple enemies during teamfights can make it easier for your team to kill them. It also has synergy with Slithereen Crush, as that move deals physical damage which is reduced by armor. Amplify Damage also makes you a reliable counter against invisible heroes like Riki and Weaver, since the True Sight it grants will dispel their invisibility until the duration ends.
 * Ability: Target Unit
 * Affects: Enemy Heroes
 * Armor Reduction: 8 / 14 / 20
 * Duration: 25
 * Mana Cost: 25
 * Cooldown: 10