1Round 1
Early Detonation means less time reloading, more time blowing things up. With Heartbeat Sensor so you have the opportunity to finish opponents around corners.
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2Round 2
You want Stacked Sticks as early as possible because the improved radius sets more people on fire. If you have extra cash you can fill in with ability power and lifesteal.
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3Round 3
Now you get your big Dynamite upgrade. You'll be able to more strategically block off points or annoy backlines.
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4Round 4
With all the blasting, there's a good chance players are spending a lot of time burning, Cybervenom will now reduce their healing.
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5Round 5
Incendiary Blasts now gives you more burning. Buff ability damage, focus burning enemies.
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6Round 6
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7Round 7
I tend to use Double Barrelled for more chances of burning, retreating, and hitting multiple sticky dynamites and enemies, but this last pick is up to your playstyle.