Cairne, in this design, is intended to be capable of pushing into the frontline, and laying down crowd control amidst the enemy team, without worrying too much about his own demise. His damage overall isn't anything to write home about unless he is talented for such. Heroic Strike is intended to make him a decent enough threat on his own, but if outnumbered and repeatedly CC'd himself, he can be taken down.Plainsrunning is his gapcloser, even when taking damage he still moves quicker than most heroes, and when talented correctly it's potentially a manual version of the Butcher's charge. However, if stunned or rooted long enough, Plainsrunning ends. And Cairne needs several seconds to get going. In this case I'd recommend being wary of hard CC to keep your speed buff up, at least long enough to enter the fray and put his toolkit to good use as your team mops up.Endurance Aura, particularly when given a few talent buffs, is a central piece of Cairne's toolkit. It won't help stave off burst, but it'll act as a weaker form of Muradin's Second Wind that can be granted to the whole team. In the early game, this enables Cairne, his lane partner and mercenaries to absorb more damage safely even without a dedicated healer. This can free up the team's support to instead dedicate themselves either to another lane, or aid Cairne in a different way.His two heroics embody different warrior characteristics. Honour guard leans more towards being a bruiser type, or lane pushing potential, as overall this heroic allows Cairne to deal far more damage and add additional bodies to a team fight. But this comes at a cost to his own survivability and tankiness. Reincarnation meanwhile enables Cairne to make riskier plays than even more durable warriors. As an example, Cairne could engage with two enemy heroes, killing one whilst wounding the other before dying. But upon reincarnating, Cairne can chase down and finish off the wounded enemy. Though reincarnated deaths still grant the enemy with XP, in the late game map presence is more important, Reincarnation in this way could force the game to become a 3v5, whereas another warrior in the same situation result in the match turning into a 4v4. While even a Johanna with her lv20 shield can still be killed outright, Cairne can absorb most of an enemy team's burst, die, let the worst of it soar over his head before getting back up for round 2.His talents would offer two routes, much like his heroics, at the very least. One leaning more towards pushing, besieging and dealing damage, but another for being the damage sponge in a team fight whilst laying down crowd control into the enemy team.Plainsrunning would initially seem very potent, but the start up time could make it harder to pull off, especially in the midst of a fight. It's worth noting that mounting takes two seconds, Plainsrunning would require more time than that. Additionally, stutter stepping your auto attacks and abilities would be borderline required if an expert Cairne player wanted maximum up time on the speed boost. But as mentioned, an enemy team with any amount of stuns (Unless you have a support with Cleanse with extremely good reaction times) could put an end to his sprinting around. To aid in this, several talents and one of his heroics compensates and allows Plainsrunning more freedom in activation, allowing it to be used similarly to a charge during a fight, or used as an escape. Though if the enemy is chasing you for more than five seconds, uhm, well... they shouldn't be anyway if they can't catch you by then!Cairne could potentially be great for taking mercs, particularly with a near permanent honour guard healing him and soaking damage for him. Speaking of mercs, the Heroic Strike trait 'Cut them down!' is my, probably vain, attempt at making a merc orientated talent potentially good VS heroes as well. If they happen to be near one of their own minions or mercs, rather than hitting the hero with HS, you would do well to instead hit the nearby minion/merc for extra damage! A bit fiddly to pull off, and situational, similar to Kael's Living Bomb combo, but potentially deadly, or just a great poking tool in lane.And speaking of lanes; Cairne would be a hard target to budge with so much damage reduction, high health and regeneration. But if he overextends and is caught out without support, he doesn't have much in the way of escape tools in the early game. Particularly if he's being pinned from the front and back between enemy heroes. But in reverse, if the enemy pushes too hard against Cairne, his war stomp and heroic strike, coupled with the aid of towers, can cause some very real damage. Though his abilities are very mana hungry, encouraging sparse but potent use.If Call to Arms is taken, you could even play the Braves akin to Lost Vikings, soaking XP from other lanes, harassing enemy heroes. The Sunwalker in particular, with it's heal and damage bonus, acts as a beefier version of Azmodan's Demon General, in a manner of speaking, and could enable a hard push in one lane, whilst the enemy is occupied by Cairne, the Archer and the rest of your team.However, the Braves do not remain around for long if Cairne dies. So his safety must still be prioritised above the Braves. Taking Call to Arms does not entirely change Cairne into a different version of the Vikings after all.