Cyclops of Eternal Fury
Anthem effects usually pump power or grant evasion; this one hands the whole team the single keyword that converts a board commitment into immediate pressure. Haste is normally a one-creature affair stapled to an aggressive body, so distributing it across everything you control as a static effect rewrites the math of every play that puts a creature onto the battlefield: a mana dork ramps the turn it lands, a token swings the turn it appears, a flickered or reanimated body attacks without paying the customary one-turn tax. The 5/3 frame is the giveaway that this was built for a deck already racing rather than one looking to grind: it trades down to almost any removal and contributes nothing on defense. Being an enchantment creature only widens that exposure, since it answers to both creature removal and enchantment removal rather than ducking either. Where it earns the slot is the engine read, not the attack step. The value is the suspended summoning-sickness tax on a board that refills faster than an opponent can answer it: each new body comes online instantly, so the haste enchantment turns recursion, ramp, and token production into a faucet of attackers rather than a row of creatures waiting their turn. A poor blocker that makes everything around it an immediate threat is the trade the design is built on.
