Xbalanque quickly became one of my favorite gods, because he's extremely fun to play and is really hard to catch. If he gets fed, he'll deal tons of damage and wipe out squishies before they even see him.
Many people consider him "op", but that's not true. Every god can be op, if you know how to play them.
I'll cover his abilities and tell you what you can/should do.
Passive: You literally stack gods. For each enemy you kill, you get 5 physical power.
You can reach the maximum of 6 stacks, so at 6 kills, you get +30 physical power. This can and will give a huge advantage.
Branching Bola: This is a buff you can toggle. If you activate it, every basic attack will cost mana, increasing by level. Critical hits are affected by your 1, so activate it whenever you're facing an enemy. When you hit an opponent, it'll split in 2 smaller bolas, dealing 30% of your damage (these bolas always hit other enemys). If overused, you'll end up with a manaless Xbalanque, which is basically your death. If you need, you can stack Transcendence. Use this ability whenever you need a quicker waveclear or if you need to delete an enemy.
Poison Darts: When activated, you shoot out 10 darts, which will poison your enemies, dealing damage over time. They can be hit by multiple darts, but they deal reduced damage. Use this to poke and to chase down fleeing foes, since it'll slow them.
This will make it easier for you to hit your basic attacks. If you want to take a jungle
camp, try to go as close as possible, so you'll hit the big one with every dart.
Rising Jaguar: If used, you'll rush forward and shoot out one dart for each enemy nearby. This ability will deal bonus damage when they are poisoned by your 2, Poison Darts. This skill is your main escape. I'd personally never use it for waveclear.
On cooldown, you're a dead man/jaguar. Alternatively, this may be used for chasing, but be sure there are no enemies nearby which will kill you afterwards.
!WARNING! You aren't always CC-Immune, it will start without it, so you can't use it while crippled.
Darkest of Nights: This ultimate will block the vision of your enemies for 3 seconds. When this ability ends, every moving enemy is stunned for 1,5 seconds.
While active, your basic attack range is increased, you'll snipe them from your base.
No I'm serious, your range is extremely high with this thing. You can yell "360 noscope" when you kill someone with it. Also, your movement speed is increased while active, making it also a pretty decent chase/escape tool. This ultimate makes Xbalanque so good in teamfights, since your enemies won't see a single thing. You can also save your allies.
I choose Ninja Tabi over Warrior Tabi, because I just need more attack speed, since you won't have that much.
Second, I take Hastened Fatalis, because I really love it's passive, your already absurd chasing potential is even higher, making it almost impossible for the enemy to escape.
Next, Asi. It'll give you some nice penetration and lifesteal, and even more when below 35% health. The nerf to it doesn't matter, I mean, 20% attack speed is totally fine to me.
Your next items should be Rage and Deathbringer, you know, crits.
Rage will stack your crit chance and Deathbringer will make them deal even more damage.
I personally don't like Malice, some people take it over Rage, but it gives less Crit Chance and I hate his passive. You won't have that much physical damage, so it's pretty useless I'd say. But hey, that's my opinion.
At last, you may take Jotunn's Wrath or Titan's Bane, whatever you feel like. If you need more cooldown reduction, take Jotunn, if the enemies really hate you and stack armor, take Titan's.
Alternatively, you may take Transcendence at first, so you can stack mana. Then you can either ignore boots or you just don't buy Jotunn/Titan.
I never take it, because I don't like stacking in Arena.
Always take Sprint whenever you have some spare 300gold. Then upgrade it to Greater Sprint whenever you feel like.
If needed, take Purification Beads or Greater Aegis / Aegis Pendant.