Galvanic Overcast (Recharge 5–6). When the blastseeker casts lightning bolt or thunderwave, it can roll a die. On an odd number, the blastseeker takes 9 (2d8) force damage. On an even number, the spell also deals 9 (2d8) lightning damage to each target that fails its saving throw.
Heart of the Storm. When the blastseeker casts lightning bolt or thunderwave, all other creatures within 10 feet of the blastseeker each take 3 lightning damage.
Gust-Propelled Leap. The blastseeker can use a bonus action to fly up to 10 feet without provoking opportunity attacks.
Innate Spellcasting. The blastseeker's innate spellcasting ability is Intelligence (spell save DC 15, +7 to hit with spell attacks). The blastseeker can innately cast the following spells, requiring no components other than its Izzet gear, which doesn't function for others:
1/day: stoneskin
3/day each: levitate, lightning bolt, thunderwave
Spear. Melee or Ranged Weapon Attack: +3 to hit, reach 5 ft. or range 20/60 ft., one target. Hit:3 (1d6) piercing damage, or 4 (1d8) piercing damage if used with two hands to make a melee attack.
While chemisters focus on inventing new tools, weapons, and other devices for the guild to use, the role of a blastseeker is to put those devices to work. Despite the name, not all such devices produce explosions, but all the most interesting ones (from the Izzet perspective) do.